Fixed compilation warnings/errors under C++ mode

git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@1569 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjsip/src/pjsip-ua/sip_reg.c b/pjsip/src/pjsip-ua/sip_reg.c
index 0a8e6d0..fda28d7 100644
--- a/pjsip/src/pjsip-ua/sip_reg.c
+++ b/pjsip/src/pjsip-ua/sip_reg.c
@@ -739,8 +739,8 @@
 		     * server may not return it.
 		     */
 
-		    uri1 = pjsip_uri_get_uri(contact[i]->uri);
-		    uri2 = pjsip_uri_get_uri(our_contact->uri);
+		    uri1=(const pjsip_uri*)pjsip_uri_get_uri(contact[i]->uri);
+		    uri2=(const pjsip_uri*)pjsip_uri_get_uri(our_contact->uri);
 		    if (pjsip_uri_cmp(PJSIP_URI_IN_CONTACT_HDR, uri1, uri2)==0)
 		    {
 			has_our_contact = PJ_TRUE;