diff --git a/nsprpub/admin/repackage.sh b/nsprpub/admin/repackage.sh
index 7bbfa58d61af9..0df32218288a0 100755
--- a/nsprpub/admin/repackage.sh
+++ b/nsprpub/admin/repackage.sh
@@ -64,10 +64,10 @@
 # 
 # ------------------------------------------------------------------
 
-FROMTOP=/share/builds/components/nspr20/v4.8
-TOTOP=./v4.8
-NSPRDIR=nspr-4.8
-SOURCETAG=NSPR_4_8_RTM
+FROMTOP=/share/builds/components/nspr20/v4.8.1
+TOTOP=./v4.8.1
+NSPRDIR=nspr-4.8.1
+SOURCETAG=NSPR_4_8_1_RTM
 
 #
 # enumerate Unix object directories on /s/b/c
diff --git a/nsprpub/config/prdepend.h b/nsprpub/config/prdepend.h
index df72c56882d21..55444c40b3aa8 100644
--- a/nsprpub/config/prdepend.h
+++ b/nsprpub/config/prdepend.h
@@ -42,3 +42,4 @@
  */
 
 #error "Do not include this header file."
+
diff --git a/nsprpub/configure b/nsprpub/configure
index 542542d886bd7..6c923af51cc8f 100755
--- a/nsprpub/configure
+++ b/nsprpub/configure
@@ -695,7 +695,7 @@ test "$host_alias" != "$target_alias" &&
 
 MOD_MAJOR_VERSION=4
 MOD_MINOR_VERSION=8
-MOD_PATCH_VERSION=0
+MOD_PATCH_VERSION=1
 NSPR_MODNAME=nspr20
 _HAVE_PTHREADS=
 USE_PTHREADS=
@@ -4232,6 +4232,7 @@ EOF
         DSO_LDOPTS=-DEBUG -DEBUGTYPE:CV
     fi
     _DEBUG_FLAGS=-Zi
+    _OPTIMIZE_FLAGS=-O2
     ;;
 
 *-ncr-sysv*)
@@ -4505,17 +4506,17 @@ EOF
         _OPTIMIZE_FLAGS="$_OPTIMIZE_FLAGS -Olimit 4000"
         ac_safe=`echo "machine/builtins.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for machine/builtins.h""... $ac_c" 1>&6
-echo "configure:4509: checking for machine/builtins.h" >&5
+echo "configure:4510: checking for machine/builtins.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 4514 "configure"
+#line 4515 "configure"
 #include "confdefs.h"
 #include <machine/builtins.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:4519: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:4520: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -5164,7 +5165,7 @@ case $target in
     ;;
 *)
     echo $ac_n "checking for dlopen in -ldl""... $ac_c" 1>&6
-echo "configure:5168: checking for dlopen in -ldl" >&5
+echo "configure:5169: checking for dlopen in -ldl" >&5
 ac_lib_var=`echo dl'_'dlopen | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -5172,7 +5173,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-ldl  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 5176 "configure"
+#line 5177 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -5183,7 +5184,7 @@ int main() {
 dlopen()
 ; return 0; }
 EOF
-if { (eval echo configure:5187: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5188: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -5200,17 +5201,17 @@ if eval "test \"`echo '$ac_cv_lib_'$ac_lib_var`\" = yes"; then
   echo "$ac_t""yes" 1>&6
   ac_safe=`echo "dlfcn.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for dlfcn.h""... $ac_c" 1>&6
-echo "configure:5204: checking for dlfcn.h" >&5
+echo "configure:5205: checking for dlfcn.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5209 "configure"
+#line 5210 "configure"
 #include "confdefs.h"
 #include <dlfcn.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:5214: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:5215: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -5243,13 +5244,13 @@ esac
 
 if test $ac_cv_prog_gcc = yes; then
     echo $ac_n "checking whether ${CC-cc} needs -traditional""... $ac_c" 1>&6
-echo "configure:5247: checking whether ${CC-cc} needs -traditional" >&5
+echo "configure:5248: checking whether ${CC-cc} needs -traditional" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gcc_traditional'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
     ac_pattern="Autoconf.*'x'"
   cat > conftest.$ac_ext <<EOF
-#line 5253 "configure"
+#line 5254 "configure"
 #include "confdefs.h"
 #include <sgtty.h>
 Autoconf TIOCGETP
@@ -5267,7 +5268,7 @@ rm -f conftest*
 
   if test $ac_cv_prog_gcc_traditional = no; then
     cat > conftest.$ac_ext <<EOF
-#line 5271 "configure"
+#line 5272 "configure"
 #include "confdefs.h"
 #include <termio.h>
 Autoconf TCGETA
@@ -5291,12 +5292,12 @@ fi
 for ac_func in lchown strerror
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:5295: checking for $ac_func" >&5
+echo "configure:5296: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5300 "configure"
+#line 5301 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -5319,7 +5320,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:5323: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5324: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -5360,7 +5361,7 @@ hpux*)
 if test -z "$GNU_CC"; then
 
     echo $ac_n "checking for +Olit support""... $ac_c" 1>&6
-echo "configure:5364: checking for +Olit support" >&5
+echo "configure:5365: checking for +Olit support" >&5
 if eval "test \"`echo '$''{'ac_cv_hpux_usable_olit_option'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -5399,7 +5400,7 @@ darwin*)
 *)
     
 echo $ac_n "checking for pthread_create in -lpthreads""... $ac_c" 1>&6
-echo "configure:5403: checking for pthread_create in -lpthreads" >&5
+echo "configure:5404: checking for pthread_create in -lpthreads" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5421,7 +5422,7 @@ echo "
         echo "$ac_t""no" 1>&6
         
 echo $ac_n "checking for pthread_create in -lpthread""... $ac_c" 1>&6
-echo "configure:5425: checking for pthread_create in -lpthread" >&5
+echo "configure:5426: checking for pthread_create in -lpthread" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5443,7 +5444,7 @@ echo "
         echo "$ac_t""no" 1>&6
         
 echo $ac_n "checking for pthread_create in -lc_r""... $ac_c" 1>&6
-echo "configure:5447: checking for pthread_create in -lc_r" >&5
+echo "configure:5448: checking for pthread_create in -lc_r" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5465,7 +5466,7 @@ echo "
         echo "$ac_t""no" 1>&6
         
 echo $ac_n "checking for pthread_create in -lc""... $ac_c" 1>&6
-echo "configure:5469: checking for pthread_create in -lc" >&5
+echo "configure:5470: checking for pthread_create in -lc" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5597,7 +5598,7 @@ if test -n "$USE_PTHREADS"; then
       rm -f conftest*
    ac_cv_have_dash_pthread=no
    echo $ac_n "checking whether ${CC-cc} accepts -pthread""... $ac_c" 1>&6
-echo "configure:5601: checking whether ${CC-cc} accepts -pthread" >&5
+echo "configure:5602: checking whether ${CC-cc} accepts -pthread" >&5
    echo 'int main() { return 0; }' | cat > conftest.c
    ${CC-cc} -pthread -o conftest conftest.c > conftest.out 2>&1
    if test $? -eq 0; then
@@ -5620,7 +5621,7 @@ echo "configure:5601: checking whether ${CC-cc} accepts -pthread" >&5
 			    ac_cv_have_dash_pthreads=no
     if test "$ac_cv_have_dash_pthread" = "no"; then
 	    echo $ac_n "checking whether ${CC-cc} accepts -pthreads""... $ac_c" 1>&6
-echo "configure:5624: checking whether ${CC-cc} accepts -pthreads" >&5
+echo "configure:5625: checking whether ${CC-cc} accepts -pthreads" >&5
     	echo 'int main() { return 0; }' | cat > conftest.c
 	    ${CC-cc} -pthreads -o conftest conftest.c > conftest.out 2>&1
     	if test $? -eq 0; then
diff --git a/nsprpub/configure.in b/nsprpub/configure.in
index 50cecd44a9ca7..e6b0d9c06fe5e 100644
--- a/nsprpub/configure.in
+++ b/nsprpub/configure.in
@@ -50,7 +50,7 @@ dnl = Defaults
 dnl ========================================================
 MOD_MAJOR_VERSION=4
 MOD_MINOR_VERSION=8
-MOD_PATCH_VERSION=0
+MOD_PATCH_VERSION=1
 NSPR_MODNAME=nspr20
 _HAVE_PTHREADS=
 USE_PTHREADS=
@@ -1684,6 +1684,7 @@ tools are selected during the Xcode/Developer Tools installation.])
         DSO_LDOPTS=-DEBUG -DEBUGTYPE:CV
     fi
     _DEBUG_FLAGS=-Zi
+    _OPTIMIZE_FLAGS=-O2
     ;;
 
 *-ncr-sysv*)
diff --git a/nsprpub/lib/libc/include/plbase64.h b/nsprpub/lib/libc/include/plbase64.h
index ac07e83735141..d21ff5d77ec75 100644
--- a/nsprpub/lib/libc/include/plbase64.h
+++ b/nsprpub/lib/libc/include/plbase64.h
@@ -57,6 +57,10 @@ PR_BEGIN_EXTERN_C
  * be terminated with an extra null character.  It is the caller's 
  * responsibility to free the result when it is allocated.  A null is returned 
  * if the allocation fails.
+ *
+ * NOTE: when calculating ((srclen + 2)/3)*4), first ensure that
+ *     srclen <= (PR_UINT32_MAX/4) * 3
+ * to avoid PRUint32 overflow.
  */
 
 PR_EXTERN(char *)
@@ -83,6 +87,12 @@ PL_Base64Encode
  * result *will* be terminated with an extra null character.  It is the
  * caller's responsibility to free the result when it is allocated.  A null
  * is retuned if the allocation fails, or if the source is not well-coded.
+ *
+ * NOTE: when calculating (srclen * 3)/4, first ensure that 
+ *     srclen <= PR_UINT32_MAX/3
+ * to avoid PRUint32 overflow.  Alternatively, calculate
+ *     (srclen/4) * 3 + ((srclen%4) * 3)/4
+ * which is equivalent but doesn't overflow for any value of srclen.
  */
 
 PR_EXTERN(char *)
diff --git a/nsprpub/lib/libc/src/base64.c b/nsprpub/lib/libc/src/base64.c
index 0f6127574f0b3..e3fd80d7d6186 100644
--- a/nsprpub/lib/libc/src/base64.c
+++ b/nsprpub/lib/libc/src/base64.c
@@ -38,7 +38,8 @@
 #include "plbase64.h"
 #include "prlog.h" /* For PR_NOT_REACHED */
 #include "prmem.h" /* for malloc / PR_MALLOC */
-#include "plstr.h" /* for PL_strlen */
+
+#include <string.h> /* for strlen */
 
 static unsigned char *base = (unsigned char *)"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
@@ -150,7 +151,13 @@ PL_Base64Encode
 {
     if( 0 == srclen )
     {
-        srclen = PL_strlen(src);
+        size_t len = strlen(src);
+        srclen = len;
+        /* Detect truncation. */
+        if( srclen != len )
+        {
+            return (char *)0;
+        }
     }
 
     if( (char *)0 == dest )
@@ -389,7 +396,13 @@ PL_Base64Decode
 
     if( 0 == srclen )
     {
-        srclen = PL_strlen(src);
+        size_t len = strlen(src);
+        srclen = len;
+        /* Detect truncation. */
+        if( srclen != len )
+        {
+            return (char *)0;
+        }
     }
 
     if( srclen && (0 == (srclen & 3)) )
@@ -410,8 +423,7 @@ PL_Base64Decode
     if( (char *)0 == dest )
     {
         /* The following computes ((srclen * 3) / 4) without overflow. */
-        PRUint32 rem = srclen % 4;
-        PRUint32 destlen = (srclen / 4) * 3 + (rem * 3) / 4;
+        PRUint32 destlen = (srclen / 4) * 3 + ((srclen % 4) * 3) / 4;
         dest = (char *)PR_MALLOC(destlen + 1);
         if( (char *)0 == dest )
         {
diff --git a/nsprpub/lib/libc/src/strlen.c b/nsprpub/lib/libc/src/strlen.c
index 5cbc2b7ab1d2b..e03f7d25825ae 100644
--- a/nsprpub/lib/libc/src/strlen.c
+++ b/nsprpub/lib/libc/src/strlen.c
@@ -53,7 +53,10 @@ PL_strlen(const char *str)
      * we don't have ultra long strings that overflow an int32
      */ 
     if( sizeof(PRUint32) < sizeof(size_t) )
-        PR_ASSERT(l <= PR_INT32_MAX);
+    {
+        if( l > PR_INT32_MAX )
+            PR_Assert("l <= PR_INT32_MAX", __FILE__, __LINE__);
+    }
 
     return (PRUint32)l;
 }
diff --git a/nsprpub/pr/include/md/_symbian.cfg b/nsprpub/pr/include/md/_symbian.cfg
index 09a2466984ef6..2db9af7312cff 100644
--- a/nsprpub/pr/include/md/_symbian.cfg
+++ b/nsprpub/pr/include/md/_symbian.cfg
@@ -87,13 +87,53 @@
 #define PR_ALIGN_OF_FLOAT   4
 #define PR_ALIGN_OF_POINTER 4
 #define PR_ALIGN_OF_WORD    4
-#ifdef __WINS__
-#define PR_ALIGN_OF_INT64   4
-#define PR_ALIGN_OF_DOUBLE  4
-#else
 #define PR_ALIGN_OF_INT64   8
 #define PR_ALIGN_OF_DOUBLE  8
-#endif
+
+#define PR_BYTES_PER_WORD_LOG2   2
+#define PR_BYTES_PER_DWORD_LOG2  3
+
+#elif defined(__WINS__)
+
+#define IS_LITTLE_ENDIAN 1
+#undef  IS_BIG_ENDIAN
+
+#define PR_BYTES_PER_BYTE   1
+#define PR_BYTES_PER_SHORT  2
+#define PR_BYTES_PER_INT    4
+#define PR_BYTES_PER_INT64  8
+#define PR_BYTES_PER_LONG   4
+#define PR_BYTES_PER_FLOAT  4
+#define PR_BYTES_PER_DOUBLE 8
+#define PR_BYTES_PER_WORD   4
+#define PR_BYTES_PER_DWORD  8
+
+#define PR_BITS_PER_BYTE    8
+#define PR_BITS_PER_SHORT   16
+#define PR_BITS_PER_INT     32
+#define PR_BITS_PER_INT64   64
+#define PR_BITS_PER_LONG    32
+#define PR_BITS_PER_FLOAT   32
+#define PR_BITS_PER_DOUBLE  64
+#define PR_BITS_PER_WORD    32
+
+#define PR_BITS_PER_BYTE_LOG2   3
+#define PR_BITS_PER_SHORT_LOG2  4
+#define PR_BITS_PER_INT_LOG2    5
+#define PR_BITS_PER_INT64_LOG2  6
+#define PR_BITS_PER_LONG_LOG2   5
+#define PR_BITS_PER_FLOAT_LOG2  5
+#define PR_BITS_PER_DOUBLE_LOG2 6
+#define PR_BITS_PER_WORD_LOG2   5
+
+#define PR_ALIGN_OF_SHORT   2
+#define PR_ALIGN_OF_INT     4
+#define PR_ALIGN_OF_LONG    4
+#define PR_ALIGN_OF_FLOAT   4
+#define PR_ALIGN_OF_POINTER 4
+#define PR_ALIGN_OF_WORD    4
+#define PR_ALIGN_OF_INT64   4
+#define PR_ALIGN_OF_DOUBLE  4
 
 #define PR_BYTES_PER_WORD_LOG2   2
 #define PR_BYTES_PER_DWORD_LOG2  3
diff --git a/nsprpub/pr/include/md/_symbian.h b/nsprpub/pr/include/md/_symbian.h
index 7393a958ac6f2..1fef115520e0c 100644
--- a/nsprpub/pr/include/md/_symbian.h
+++ b/nsprpub/pr/include/md/_symbian.h
@@ -45,7 +45,9 @@
  */
 
 #define _PR_SI_SYSNAME  "SYMBIAN"
-#ifdef __arm__
+#if defined(__WINS__)
+#define _PR_SI_ARCHITECTURE "i386"
+#elif defined(__arm__)
 #define _PR_SI_ARCHITECTURE "arm"
 #else
 #error "Unknown CPU architecture"
diff --git a/nsprpub/pr/include/prinit.h b/nsprpub/pr/include/prinit.h
index 6ce57a81e02a9..57b4c36cf8458 100644
--- a/nsprpub/pr/include/prinit.h
+++ b/nsprpub/pr/include/prinit.h
@@ -63,11 +63,11 @@ PR_BEGIN_EXTERN_C
 ** The format of the version string is
 **     "<major version>.<minor version>[.<patch level>] [<Beta>]"
 */
-#define PR_VERSION  "4.8"
+#define PR_VERSION  "4.8.1 Beta"
 #define PR_VMAJOR   4
 #define PR_VMINOR   8
-#define PR_VPATCH   0
-#define PR_BETA     PR_FALSE
+#define PR_VPATCH   1
+#define PR_BETA     PR_TRUE
 
 /*
 ** PRVersionCheck
diff --git a/nsprpub/pr/src/md/windows/ntmisc.c b/nsprpub/pr/src/md/windows/ntmisc.c
index 289c19bba0c52..ce3c587bd497d 100644
--- a/nsprpub/pr/src/md/windows/ntmisc.c
+++ b/nsprpub/pr/src/md/windows/ntmisc.c
@@ -840,6 +840,15 @@ PRStatus _MD_WindowsGetSysInfo(PRSysInfo cmd, char *name, PRUint32 namelen)
             							osvi.dwMinorVersion);
 			}
 			break;
+#ifdef VER_PLATFORM_WIN32_CE
+    case VER_PLATFORM_WIN32_CE:
+			if (PR_SI_SYSNAME == cmd)
+				(void)PR_snprintf(name, namelen, "Windows_CE");
+			else if (PR_SI_RELEASE == cmd)
+				(void)PR_snprintf(name, namelen, "%d.%d",osvi.dwMajorVersion, 
+            							osvi.dwMinorVersion);
+			break;
+#endif
    		default:
 			if (PR_SI_SYSNAME == cmd)
 				(void)PR_snprintf(name, namelen, "Windows_Unknown");
diff --git a/nsprpub/pr/src/misc/prtrace.c b/nsprpub/pr/src/misc/prtrace.c
index 67208f37ee8b1..762dd82153947 100644
--- a/nsprpub/pr/src/misc/prtrace.c
+++ b/nsprpub/pr/src/misc/prtrace.c
@@ -516,7 +516,7 @@ PR_IMPLEMENT(void)
         case PRTraceUnLockHandles :
             PR_LOG( lm, PR_LOG_DEBUG,
                 ("PRSetTraceOption: PRTraceUnLockHandles"));
-            PR_Lock( traceLock );
+            PR_Unlock( traceLock );
             break;
 
         default:
diff --git a/nsprpub/pr/tests/vercheck.c b/nsprpub/pr/tests/vercheck.c
index 01f312265f268..55010b97d1c5c 100644
--- a/nsprpub/pr/tests/vercheck.c
+++ b/nsprpub/pr/tests/vercheck.c
@@ -52,9 +52,9 @@
 #include <stdlib.h>
 
 /*
- * This release (4.8) is backward compatible with the
- * 4.0.x, 4.1.x, 4.2.x, 4.3.x, 4.4.x, 4.5.x, 4.6.x, and
- * 4.7.x releases.  It, of course, is compatible with
+ * This release (4.8.1) is backward compatible with the
+ * 4.0.x, 4.1.x, 4.2.x, 4.3.x, 4.4.x, 4.5.x, 4.6.x, 4.7.x,
+ * and 4.8 releases.  It, of course, is compatible with
  * itself.
  */
 static char *compatible_version[] = {
@@ -63,7 +63,8 @@ static char *compatible_version[] = {
     "4.5", "4.5.1",
     "4.6", "4.6.1", "4.6.2", "4.6.3", "4.6.4", "4.6.5",
     "4.6.6", "4.6.7", "4.6.8",
-    "4.7", "4.7.1", "4.7.2", "4.7.3", PR_VERSION
+    "4.7", "4.7.1", "4.7.2", "4.7.3", "4.7.4",
+    "4.8", PR_VERSION
 };
 
 /*