Fixed bug in remote payload type search

git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@302 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjmedia/src/pjmedia/session.c b/pjmedia/src/pjmedia/session.c
index ab9e5e9..958cd10 100644
--- a/pjmedia/src/pjmedia/session.c
+++ b/pjmedia/src/pjmedia/session.c
@@ -202,7 +202,7 @@
 	    if (!r_attr)
 		continue;
 
-	    if (pjmedia_sdp_attr_get_rtpmap(attr, &r_rtpmap) != PJ_SUCCESS)
+	    if (pjmedia_sdp_attr_get_rtpmap(r_attr, &r_rtpmap) != PJ_SUCCESS)
 		continue;
 
 	    if (!pj_stricmp(&rtpmap->enc_name, &r_rtpmap.enc_name) &&