Remove SDP from 487 response when incoming INVITE comes without SDP and we are sending offer in 18x response

git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@1564 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjsip/src/pjsip-ua/sip_inv.c b/pjsip/src/pjsip-ua/sip_inv.c
index 1d81c78..48ddc6c 100644
--- a/pjsip/src/pjsip-ua/sip_inv.c
+++ b/pjsip/src/pjsip-ua/sip_inv.c
@@ -2075,8 +2075,11 @@
 	tdata = invite_tsx->last_tx;
 
 	status = pjsip_dlg_modify_response(inv->dlg, tdata, 487, NULL);
-	if (status == PJ_SUCCESS)
+	if (status == PJ_SUCCESS) {
+	    /* Remove the message body */
+	    tdata->msg->body = NULL;
 	    pjsip_dlg_send_response(inv->dlg, invite_tsx, tdata);
+	}
     }
 
     if (invite_tsx)