Unexpected authentication across trusted domains

Hello,

We have a Lab domain that trusts our Production domain.
In the lab domain – OCS has been installed which is using the default service account of Lab\RTCService.
Production domain’s OCS also uses the default service account – Prod\RTCService
The problem is that OCS in the lab domain is trying to authenticate the RTCService credentials against Production domain – which is obviously locking the account in Production!

Any thoughts on why this would be happening?

Thanks!