XKB custom dead key combinations

[TRANS]

Hi--

I have been doing some research on XKB and Xmodmap without very much
luck. I want to create a custom keyboard map that uses sequential key
combinations to produce a single key. For example, if I press 'k' and
then 'k' again I want the character 't' to be result. So it's sort of
like dead keys but customized deak keys.

Is there anyway to do this?

Thanks,
Trans