I set the mentioned below capabilities for Media type audio but still having a problem "480 Temporarily Not Available" please give me any clue,Another user is not able to receive an INVITE request.

<ACCEPT_CONTACT value=\"*;mobility=mobile;media=audio\" />\
<ALLOW_EVENTS value=\"presence\" />\
<ACCEPT value=\"audio/basic\" />\
<ACCEPT value=\"application/sdp\" /> \
<LINE name=\"m\" value=\"audio 30000 RTP/AVP 8\" />\

Little modification is done in creating CSdpMediaField.Like i'm setting EMediaAudio and EProtocolRtpAvp as a media type and protocol.so the INVITE request is looking like that...

INVITE sip:5000@ SIP/2.0
Via: SIP/2.0/UDP;branch=z9hG4bKbc96991ff4d4e6f7cde5defec3d84efa
Via: SIP/2.0/UDP;branch=z9hG4bKdt7q2r3ka9hc77gpn13m5nu;rport
From: <sip:5001@>;tag=goaa2r58p5hc6kafn13u
To: <sip:5000@>
Contact: <sip:5001@>
CSeq: 1114 INVITE
Call-ID: r3-xrc0AoIfvfbx7rJUBvv28Xz8WqC
Max-Forwards: 69
Content-Type: application/sdp
Accept: application/sdp
Content-Length: 141

o=5000 523427878 2890844532 IN IP4
c=IN IP4
t=0 0
m=audio 30000 RTP/AVP 8
a=rtpmap:8 PCMA/8000/1

"480 Temporarily Not Available" is received in response.Any clue on that would be appreciable.Alot of threads are on forum but no boday post the solution of it and this is a big road block for developing RTP part of VOIP application.

Thanks in advance,