Two versions on same server?

[Jim McAtee]

Can I run two different versions of MySQL on the same server?  I've got a 
commercial application for which the vendor will only support MySQL 3.x 
and makes no guarantees if running MySQL 4.  But I'd like to migrate a 
number of our own web applications to MySQL 4.  My choices are take my 
chances with the other app, run MySQL on a second machine (not an option 
at the current time) or else run two instances of MySQL, different 
versions, both on the same machine.