We have a login script drive mapping that works great when the user is in the same container as their server but fails for most, if not all, users located in a different container that their server.
What seems to be happening is the login processor picks up the fully qualified server name but then truncates it for some reason. An example of the error is:

Mapping to VOL1 (S:)
Drive S: = CRP-MIA5-SRV1_VOL1.MIA5.CRP..: \

LOGIN-LGNWNT32.DLL-890: The specified server is unknown.
LOGIN-LGNWNT32.DLL-430: The following drive mapping operation could not be completed.
The error code was 8884.

The actual fully qualified server is CRP-MIA5-SRV1.MIA5.CRP.COMPANY

The map line is picking up the server name from %MESSAGE_SERVER DS has the fully qualified host listed. The exact line is:
This used to work reliably or so it seemed - what am I missing here?