410 "Gone"

When I register using GPRS using softphone CSIPSIMPLE and I tried to call to it from other network I receive SERVICE UNAVAIBLE, but on CSIPSIMPLE I see 410/gone.

Log from asterisk:

– Called SIP/100104
– Connected line update to SIP/100105-00000049 prevented.
– Got SIP response 410 “Gone” back from
– SIP/100104-0000004a is circuit-busy

Any idea?