[Serusers] how to found SER server works like two local exchanges

Hi all, The SIP phones on the Ser server have two different define: Exchange 1: number is like 61691xxx as caller: when it calls to PSTN, dialing 0+PSTN number when it calls to 6169xxxx(expect 61691xxx), dialing 0+6169xxxx when it calls to 61691xxx, dialing only 1xxx as callee: wher PSTN and 6169xxxx(expect 61691xxx) calls, dialing 61691xxx when 61691xxx calls, dialing 1xxx Exchange 2: number is like 6169xxxx(expect 61691xxx) as caller: call callee's number as callee: wher PSTN and 6169xxxx(expect 61691xxx) calls, dialing 6169xxxx when 61691xxx calls, dialing 0+6169xxxx Using prefix() and rewriteuser() to make call mabye cause call-leg can not find. How to do that? Br, Wangji