Compose key in Ubuntu 8.10 vs. Ubuntu 9.04

[Johnny Rosenberg]

I have four machines: One with Ubuntu 8.10 and the other three with
Ubuntu 9.04. Here are some examples of the Compose key output at the
Ubuntu 9.04 vs. Ubuntu 8.10:
Combination: 9.04 - 8.10
Compose c o: © - ǒ
Compose o c: © - ©
Compose . .: ˙ - …

Well, I guess there are more differences, but these will do.
Can anyone give me some suggestions WHY this happens?

This makes the Compose key somewhat more useless in Ubuntu 9.04 than
in Ubuntu 8.10, I think, if this is a Ubuntu 8.10 vs. Ubuntu 9.04
issue, that is.

Johnny Rosenberg