exchange 2010 active sync problem

I am working on migration from exchange 2007 to 2010. Everything is working at this moment only thing which is headache is active-sync. Active-sync discovery is working great though. Can somebody direct me to correct position.

error says that: 

The Exchange ActiveSync URL was in an invalid format. It should be https://host/Microsoft-Server-ActiveSync. The URL was https://<my mailbox URL>.