diff --git a/tests/ftpserver.pl b/tests/ftpserver.pl
index 3a4a0795c6eb2985b9a876196518b6d18fe869bf..a37802d5c063fca12ad43d057677975e19917d17 100755
--- a/tests/ftpserver.pl
+++ b/tests/ftpserver.pl
@@ -3252,7 +3252,7 @@ while(1) {
         my $check = 1; # no response yet
 
         # See if there is a custom reply for the full text
-        my $fulltext = $FTPCMD . " " . $FTPARG;
+        my $fulltext = $FTPARG ? $FTPCMD . " " . $FTPARG : $FTPCMD;
         my $text = $fulltextreply{$fulltext};
         if($text && ($text ne "")) {
             sendcontrol "$text\r\n";