diff --git a/configure-plugins b/configure-plugins
index ad50232fceea0..800a653385aa1 100755
--- a/configure-plugins
+++ b/configure-plugins
@@ -56,7 +56,7 @@ generate_configh () {
     if [ ! "$oldlib" = "$lib" ]; then
       [ -n "$oldlib" ] && echo "     0"
       oldlib=$lib
-      uclib=$(echo $lib | tr '[a-z]' '[A-Z]')
+      uclib=$(echo $lib | perl -pe '$_=uc')
       echo
       echo "#define R_${uclib}_STATIC_PLUGINS \\"
       plugins="${plugins} __${uclib}"
@@ -71,7 +71,7 @@ generate_configh () {
     plg=$(echo $a | cut -d . -f 2) # plugin name
     if [ ! "$oldlib" = "$lib" ]; then
       oldlib=$lib
-      uclib=$(echo $lib | tr '[a-z]' '[A-Z]')
+      uclib=$(echo $lib | perl -pe '$_=uc')
       if [ -z "`echo ${plugins} | grep __${uclib}`" ]; then
         plugins="${plugins} __${uclib}"
         echo
@@ -90,7 +90,7 @@ generate_configmk () {
     if [ ! "$oldlib" = "$lib" ]; then
       [ -n "$oldlib" ] && printf "\n"
       oldlib=$lib
-      uclib=$(echo $lib | tr '[a-z]' '[A-Z]')
+      uclib=$(echo $lib | perl -pe '$_=uc')
       printf "STATIC_${uclib}_PLUGINS= "
       plugins="${plugins} __${uclib}"
     fi
@@ -102,7 +102,7 @@ generate_configmk () {
   # fill the holes with love
   for a in ${SHARED} ; do
     lib=$(echo $a | cut -d . -f 1) # library
-    uclib=$(echo $lib | tr '[a-z]' '[A-Z]')
+    uclib=$(echo $lib | perl -pe '$_=uc')
     if [ -z "`echo ${plugins} | grep __${uclib}`" ]; then
       plugins="${plugins} __${uclib}"
       echo "STATIC_${uclib}_PLUGINS="