diff --git a/scripts/external b/scripts/external
index c2a2b5092d..e6b1503f70 100755
--- a/scripts/external
+++ b/scripts/external
@@ -238,12 +238,12 @@ external_import_configure()
 
   rvm_ruby_url="$1"
   rvm_ruby_string="${2:-${rvm_ruby_url}}"
+  __rvm_ruby_string
 
   [[ -r "${rvm_ruby_url}" ]] ||
   case "${rvm_ruby_url}" in
     (http*) true ;;
     (*)
-      __rvm_ruby_string
       rvm_ruby_url="$(__rvm_remote_server_path "${rvm_ruby_string}.${rvm_remote_extension:-tar.bz2}" )"
       ;;
   esac