Index: channels/sip/dialplan_functions.c
===================================================================
--- channels/sip/dialplan_functions.c	(revision 310048)
+++ channels/sip/dialplan_functions.c	(working copy)
@@ -47,6 +47,13 @@
 		AST_APP_ARG(type);
 		AST_APP_ARG(field);
 	);
+		
+	/* Check for zero arguments */
+	if (ast_strlen_zero(parse)) {
+		ast_log(LOG_ERROR, "Cannot call %s without arguments\n", funcname);
+		return -1;
+	}
+
 	AST_STANDARD_APP_ARGS(args, parse);
 
 	/* Sanity check */