--- chan_siporg.c	2013-10-25 18:05:55.000000000 +0200
+++ chan_sip.c	2014-03-21 20:22:58.000000000 +0100
@@ -13842,6 +13842,12 @@
 	else /* Save for any further attempts */
 		ast_string_field_set(p, fromname, n);
 
+	/* Allow domain to be overridden */
+	if (!ast_strlen_zero(p->fromdomain))
+		d = p->fromdomain;
+	else /* Save for any further attempts */
+		ast_string_field_set(p, fromdomain, d);
+
 	ast_copy_string(tmp_l, l, sizeof(tmp_l));
 	if (sip_cfg.pedanticsipchecking) {
 		ast_escape_quoted(n, tmp_n, sizeof(tmp_n));