--- unregister-common-lisp-source~	2008-06-13 00:59:34.000000000 -0700
+++ unregister-common-lisp-source	2008-09-22 09:50:20.000000000 -0700
@@ -12,7 +12,7 @@
 
 library="$1"
 
-echo "$library" | grep -q '[^a-zA-Z0-9-]' && echo "Found special characters in $1!" && exit 42
+echo "$library" | grep -q '[^a-zA-Z0-9\+-]' && echo "Found special characters in $1!" && exit 42
 
 echo "$library" | grep -q '\.\.' && echo "Found .. in $1!" && exit 1