[Usability] mnemonics in messages dialogs shouldn't require Alt key?

[Alan Horkan <horkana maths tcd ie>]

I recently noticed that (unlike in windows) message dialogs require you to
use Alt to access the mnemonics.  Note this is restricted to simple
message dialogs and is not enabled in more complex dialogs.

so in the case of message dialogs like
_Cancel _OK
on windows you could simply hit 'C' or 'O' where as with Gnome you must
hit Alt+C or Alt+O.

Is this intentional to help avoid accidental dismissal of dialogs or
are there other downsides to this I am not seeing?
Is this something that could be enabled, I find it very comfortable and
useful?

Sincerely

Alan Horkan

http://advogato.org/person/AlanHorkan/
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