[Koha] mysql 5.0 and Koha on Gutsy (Ubuntu)

[H.S.]

Hello,

A machine running Koha (still in the setup phase, not operational yet) 
was upgraded from Fiesty to Gutsy. However, this also forced an upgrade 
of MySQL from 4.x version to 5.0.

Should there be a problem with Koha? If so, I will either try to 
downgrade MySQL on Gutsy (4.x version doesn't seem to be available for 
it, though) or maybe give Koha 3.0 a shot (if it works with MySQL 5.x).

This is for a very small community library. What is the general advice 
about Koha 3.0 for this?

thanks,
->HS