Replication services available?

[Tommy van Leeuwen <tommy@support.nl>]

Hi there,

We're planning on building a redunant (more or less) mailserver. I was
wondering if there is any replication software available for linux or
debian specific. Doesn't matter if it's commercial or gpl.

What we basically need to do is to keep 2 mailbox partitions in sync with
each other on different machines. 

I know i could write a script which cp's the diffs between the servers but
a more real-time option would be prefered. I've never actually heard of
this kind of apps for linux (or other unices) but maybe you guys outthere
know of something which is usable. 

I will probably end up using cp's anyway but you never know :)

Thanks for any hints!

Kind Regards,

Tommy