diff -r 10c522a4c93a -r 80ecb950263a libpurple/protocols/jabber/caps.c
--- a/libpurple/protocols/jabber/caps.c	Fri Jul 09 22:14:03 2010 +0000
+++ b/libpurple/protocols/jabber/caps.c	Fri Jul 09 22:49:17 2010 +0000
@@ -841,9 +841,12 @@
 static void 
 append_escaped_string(PurpleCipherContext *context, const gchar *str)
 {
-	char *tmp = g_markup_escape_text(str, -1);
-	purple_cipher_context_append(context, (const guchar *)tmp, strlen(tmp));
-	g_free(tmp);
+	if (str && *str) {
+		char *tmp = g_markup_escape_text(str, -1);
+		purple_cipher_context_append(context, (const guchar *)tmp, strlen(tmp));
+		g_free(tmp);
+	}
+
 	purple_cipher_context_append(context, (const guchar *)"<", 1);
 }