Handle case where validation command produces no output http://virtualmin.com/node/29763

useradmin/lang/en

@@ -177,6 +177,7 @@ usave_epasswd_re=Password does not match regexp $1
 usave_epasswd_dict=Password is a dictionary word
 usave_epasswd_same=Password contains or is the same as username
 usave_epasswd_mindays=Password was changed less than $1 days ago
+usave_epasswd_cmd=Password validation command failed
 usave_eothers=The user was successfully saved, but an error occured in another module : $1
 
 gedit_title=Edit Group

useradmin/user-lib.pl

@@ -1560,7 +1560,7 @@ if ($config{'passwd_prog'}) {
 		$out = &backquote_command("$config{'passwd_prog'} <$temp 2>&1");
 		}
 	if ($?) {
-		return $out;
+		return $out || $text{'usave_epasswd_cmd'};
 		}
 	}
 if ($config{'passwd_mindays'} && $uinfo ne "none") {