hi all, Thanx Klaus. Sorry to ask a question again related to the same problem. I had already tried writing the avp_write after lookup but even that causes a problem. When avp_write is done it writes the private IP address of the callee while the source_ip is the IP address of the NAT. I beleive this IP address is written because of the fix_nated_contact. Again, when avp_check is done, it returns false and again the RTP session gets started. IS there any way out to this problem. Thanx again.. Jayesh
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