Re:

[Mats Bengtsson]

> Yes of course. For example in Denmark the standard format is the A
> series (A4 etc). I should have written what I actually meant: letter is
> default paper format for the Lilypond music typesetting utilities.

Actually, A4 is default also for Lilypond, e.g. for ly2dvi. 
The letter size of the glossary is due to texi2dvi or dvips.

     /Mats