It is likely that upgrading to SLES 10 SP2 and then installing the bigsmp kernel will be the safest way. I have no idea what would happening upgrading through a major release ( 10.x to 11.x ) as it pertains to the Domino server. I'm not sure any of us can.

Also, if you plan on doing anything you should assume you will break something and need a good disaster recovery methodology. This most likely would be a reinstall and restore from backup. And so perhaps its better to upgrade Domino and the OS if they can run on a 64-bit OS.

-- Bob