The internally supported domain matches the domain suffix of type 'configured allowed domain'

Hi,

Probably some of you have seen this before as there are couple of unanswered discussions on the internet. I'm talking about a case where you should configure a overlapping domain name as allowed domain. For example sub.company.com wants to add company.com as an allowed domain. Lync allows you to do this configuration but if you restart your EDGE server, RTCSRV service doesn't start and following error appears in the Evenlog:

LS Protocol Stack EventID 14517
The server configuration validation mechanism detected some serious problems.

1 errors and 1 warnings were detected.

ERRORS:
The internally supported domain [sub.company.com] matches the domain suffix [company.com] of type 'configured allowed domain', which is not a valid configuration.

I wonder if someone knows what actually is the problem and why this is "not a valid configuration"?

Thanks

Plamen