Yes all true, but what is the conclusion? ...
Heh, good question. Conclusion: "Houston, we have a problem"

This question forced me to investigate how long we have this situation and how many languages are affected.
Well, how long?:
Since beginning on debian

, [(3.6.0.3-1.2) ... Sun, 21 Oct 2012 16:20:21 +0200]
Glest (probably) wasn't bugged because in this case were (probably) used embedded fonts.
How many languages are affected?
Currently
18 
... from 21

... every which uses "LinBiolinum_RB.ttf" (17) or "LinLibertine_RB.otf" (1).
Continuation of investigation.
Does debian have package with those fonts (stable and sid)? If yes does this package is enough nice licensed (debian's opinion)?
Answers
Yes and
Yes.
So, time to fixes:
fix for players:
apt-get install fonts-linuxlibertine
fix note for debian maintainers:
Please add "fonts-linuxlibertine" (old/dummy name "ttf-linux-libertine") to list of dependencies.
In my opinion someone trusted should inform them about that ^ and as I know softcoder and tomreyn should be best for that.
Status: [hope for fix soon]
