Two installs of mysql on ubuntu w/ identical char encoding.. but one can't handle Cyrillic

I have two separate servers which are both running mysql, but only one of them can seem to properly save Cyrillic characters. Since both mysqls are set to latin1 encoding, I'd actually expect neither of them to be capable of handling Cyrillic characters (which I think are 16-bit), but I can't complain.

On the mysql from which cy开发者_开发知识库rillic can be grabbed, the characters display from queries as question marks, but on the mysql which can't, they display as spaces.

What settings for ubuntu or mysql can I look to that would possibly be causing this discrepancy?

FWIW, this issue seemed to clear up after updating MySQL to 5.5.