diff --git a/ksh/prompt b/ksh/prompt
index f97779b..a25ce36 100755
--- a/ksh/prompt
+++ b/ksh/prompt
@@ -2,7 +2,7 @@ if [ -z "${USER}" ] ; then
 	USER=$LOGNAME
 fi
 
-if [ $USER ] && [ $USER = root ] ; then
+if [ -n "${USER}" ] && [ ${USER} = root ] ; then
 	BASE="#"
 else
 	BASE="$"