Netdom verify fails one wayy but not the other

[pehi]

Hi all;
I have a scenario where we have a domain controller and a member server in a remote site, connected by a satellite link. The DC in the remote site can verify the member server no problem, however no DC or member server anywhere else can verify it (Member servers say "The RPC server is unavailable" DC's say "Access is denied").

The strange thing is however that the DC and the server at the remote site can happily verify any other server.

This is causing centralised Apps such as SMS to fail to connect. Does anybody have any clues or workarounds?

Thanks in advance and will summarise.