[Serusers] Race Condition on CANCEL?

Hello, Im having some problems with cancelled calls. This is the scenario: U1 Proxy U2 INVITE -->>> <<--- 100 Trying INVITE -->>> <<--- 100 Trying <<--- 100 Trying CANCEL ->>> <<-- 200 Cancelling CANCEL ->> <<-- 180 Ringing <<-- 487 Cancelled <<-- 180 Ringing <<-- 200 OK (Wrong??) <<-- 200 OK My problem is that after some time waiting for "ringing", the user cancel the call. Even that proxy responses "487" it still forward the late 200 OK. Should it forward? I guess not because the transaction was destroyed, right? Can it be a configuration problem on my ser.cfg ou it can be in t_relay implementation? Thanks in advanced. Regards, Gustavo