Migration 32 to 64 bit

[Giuseppe Ravasio]

Hi, 
I'm planning the migration of our main cyrus server.
Actually the server is running cyrus imap 2.2.3 on a SuSE 9.1 i586, with about 
130Gb of mailboxes.
My idea is moving to OpenSuse 10.3 with cyrus 2.3.8 on 64bit System.

I googled a bit, but i couldn't find anything useful; i would like to know if 
there are issues moving from 32bit to 64bit and/or moving from 2.2.3 to 2.3.8
In particular i would like to minimize users impact, preserving mailstores, 
subscriptions and all seen status.

Any hints/comments/precautions???

Thanks 
G.Ravasio