Integrate Asterisk With Office Communication Server 2007


I am currently implementing Office Communication Server in my office. I have a Stand Alone OCS 2007 Standard Server and Mediation Server installed and configured. I have reached the stage to integrate the OCS with our Asterisk IP PBX System. I would like both systems to co exist and facilitate dual forking. I know that the Asterisk uses SIP over UDP and OCS uses SIP Over TCP which will be an issue. I have seen in some forums on using OpenSER and SIP X to overcome this compatibility issue. I will appreciate some assistance on accomplishing this.