[Serusers] aliases or callfwd

Hi Just wanted to get a insight as to whether its best to use aliases or callfwd for the scenario below: I have inbound pstn numbers assigned to SIP addresses. Now what i am currently doing is to assign this PSTN number as a alias to a sip address just as I would set 1111 to iqbal(a)sip.domain.com I have set 0207xxxxxxx to iqbal(a)sip.domain.com BUT I dont think this is the best way, since it then interferes with "actual" aliases that I may have ...internal ones. Can I instead use a call forward, so thay I enter the 0207 number in my forward tabel instead...or will that not work, having said this again i think it will interfere with my normal aliases. Has anyone setup a separate table/entity to do inbound number processing, and keep it separate/distinct from internally generated numbers Iqbal