Keyboard layouts

[Séamas Ó Brógáin]

I wonder whether anyone can help me with a problem concerning keyboard 
layouts (Kubuntu 6.10).

My requirement is to have the left [alt] key (rather than the right) 
function as "AltGr". I've tried all the options offered in the KDE 
Control Centre > Regional & Accessibility > Keyboard Layout > Xkb 
Options, but none of them work. (Could the physical keyboard---an old 
generic 102-key keyboard---have a bearing on this?)

The X11/xkb/symbols files are very complex, and I have failed in all 
attempts to find a reference for the syntax.

Any help would be greatly appreciated.

Séamas Ó Brógáin
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