I received this response on the official forum:


Do all players need the same language/country version?

A: No, you can play together (in any of the multiplayer modes) with everyone
who has Sacred. It does not matter if you or they use the US, UK, German or
French version of the game. CD keys are also independent of the
language/country version of the game, and the same key works with any given
version."

at this site:
http://db.gamefaqs.com/computer/doswin/file/sacred.txt

If it is true then how do we make it work?

Not true for closed or open games. Any game where you need to go through
a lobby server won't work because of the CD-key.
Only way you could possibly play together is on a local lan or through a VPN.
I heard that some poeple try to use a VPN to play together, but performance was so bad that it didn't work out....

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In other words you can't get onto the german lobby with an english cd-key and vice versa.
As i said, not my answer, it's from the german forum.
You probably read what I wrote there
Did some testing with the different lobby servers and they reject
keys which were not "supposed" to play there.
That has been confirmed by Ascaron on the german forum as well.
If you manage to get a german key (trade one or buy) you should be able
to play on a german MP game.
Really a pity that they won't allow international games for some reason.."

The question is not, Can they reason? nor, Can they talk? but, Can they suffer?
~Jeremy Bentham