[Serusers] Sending a request to a pstn gateway

I wanna call a local number, let's say 021234567 It's local, the i strip the 0 and prefix with the internationnal code I have now 3221234567 I send an ivite and i have : INVITE sip:3227321073@217.206.202.126:5060 SIP/2.0..Record-Route: <sip:027321073@82.146.123.252;ftag=965c1d6b89e086b6o0;lr=on>..Via: SIP/2.0/UDP 82.146.123.252;branch=z9hG4 bK50fe.07713b03.0..Via: SIP/2.0/UDP 192.168.2.102:5060;rport=5060;received=81.242.220.26;branch=z9hG4bK-e3b5a83e ..From: 1234 <sip:1234@finalcut.be>;tag=965c1d6b89e086b6o0.. To: <sip:027321073@finalcut.be>..Call-ID: 78d3c74f-3df84622@192.168.2.102..CSeq: 101 INVITE..Max-Forwards: 69..Contact: 1234 <sip:1234@81.242.220.26:5060>..Expires: 240..Us er-Agent: Sipura/SPA2000-2.0.10(e)..Content-Length: 465..Allow: ACK, BYE, CANCEL, INFO, INVITE, NOTIFY, OPTIONS, REFER..Supported: x-sipura..Content-Type: application/sdp.. ..v=0..o=- 1591974 1591974 IN IP4 192.168.2.102..s=-..c=IN IP4 82.146.123.252..t=0 0..m=audio 35168 RTP/AVP 18 0 2 4 8 96 97 98 100 101..a=rtpmap:18 G729a/8000..a=rtpmap:0 PCMU/8000..a=rtpmap:2 G726-32/8000..a=rtpmap:4 G723/8000..a=rtpmap:8 PCMA/8000..a=rtpmap:96 G726-40/8000..a=rtpmap:97 G726-24/8000..a=rtpmap:98 G726-16/8000..a=rtpmap:100 N SE/8000..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-15..a=ptime:30..a=sendrecv..a=direction:active..a=nortpproxy:yes.. The invite is ok, but the 'To' is 027321073 Is there a way to modiy the 'To' also? Or the problem is with my pstn provider?? Thanks Olivier