combine key to output char with xmodmap

[Emanuel Berg <embe8573@student.uu.se>]

How can I change this line

    xmodmap -e 'keycode 66=0xe2' # rebind key: CAPS (66) -> â (0xe2)

so that doesn't happen on CAPS alone (66), but instead
(and only) on M-CAPS (here, M == Alt_L)?

xev tells me M/Alt_L has has keycode 64.

-- 
underground experts united
http://user.it.uu.se/~embe8573