how can I get mysql 4.x in Gutsy

[H.S.]

Hello,

In a machine recently upgraded to Gutsy, there is a need to get the 
older version of mysql (4.x). The current version, 5.0, does not work 
Koha 2.2.9 that the machine is supposed to host.

So, how can I go about getting mysql-server-4.x on a Gutsy machine?

thanks,
->HS