--- irssi-0.8.13/src/fe-common/irc/fe-events.c	2008/11/09 23:06:37	4889
+++ irssi-0.8.13/src/fe-common/irc/fe-events.c	2009/05/15 11:54:33	5068
@@ -298,7 +298,7 @@
 
 		tmp = g_strdup(data+8);
 		len = strlen(tmp);
-		if (tmp[len-1] == 1) tmp[len-1] = '\0';
+		if (len >= 1 && tmp[len-1] == 1) tmp[len-1] = '\0';
 		printformat(server, NULL, MSGLEVEL_WALLOPS, IRCTXT_ACTION_WALLOPS, nick, tmp);
 		g_free(tmp);
 	}