diff -urN asterisk-trunk.2006.02.07.base/channels/chan_zap.c asterisk-trunk.2006.02.07.zappatch/channels/chan_zap.c
--- asterisk-trunk.2006.02.07.base/channels/chan_zap.c	2006-02-07 17:10:49.000000000 +0200
+++ asterisk-trunk.2006.02.07.zappatch/channels/chan_zap.c	2006-02-07 19:49:53.000000000 +0200
@@ -7032,7 +7032,7 @@
 				if (p.sigtype != (signalling & 0x3ffff)) {
 					ast_log(LOG_ERROR, "Signalling requested on channel %d is %s but line is in %s signalling\n", channel, sig2str(signalling), sig2str(p.sigtype));
 					destroy_zt_pvt(&tmp);
-					return tmp;
+					return NULL;
 				}
 				tmp->law = p.curlaw;
 				tmp->span = p.spanno;