[CentOS] Using a "compose key" on Centos6

Hi all!

I ran into a description of how to set up a compose key for F21 and
decided to see if it would work on  C6.

Well, the right configuration dialog exists, and I can choose a
key to use, but after completion, the compose key doesn't seem to work.

It works like a charm on Centos-7, though. If I select Right Win as
the compose key, typing <compose>ae results in "�" as I expect.

but doing the same thing on Centos-6 gives me an unadorned "ae", not
the ligature, but the individual characters. i.e., it doesn't do
anything helpful.

Since the keyboard setup dialog includes the options to define a
compose key I'm going to assume it's supposed to work, and th at I'm
just overlooking something.

Anybody got any good suggestions?

thanks!

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