HMR to replace the Contact Header values

Hi,

We need help on coming up with an HMR that will replace the contact header from the SIP Invite message received by SBC before forwarding it to the destination.

E.g.

From:

INVITE sip:88888888@abc.com:5060;user=phone;transport=UDP SIP/2.0

Via:SIP/2.0/UDP 1.1.1.1:5060;branch=z9hG4bK1mq9rt303ohjo97u8lh0.1

Max-Forwards:66

Contact:<sip:12345678@1.1.1.1:5060;transport=udp>

To:<sip:88888888@abc.com:5060;user=phone;transport=UDP>

From:<sip:12345678@abc.com;user=phone>;tag=uxxRUpXHSwg.

Call-ID:STsiaVVL2uuGl3NgBrXFUQ

CSeq:1 INVITE

Session-Expires:1800

Allow:ACK,BYE,CANCEL,INVITE,OPTIONS,UPDATE

P-Asserted-Identity:<sip:12345678@abc.com;user=phone>

Route:<sip:88888888@1.1.1.4:5060;user=phone;lr>