Ghostdog's UI Mod allows to only tweak the dialog font via the file fontdl1.bam. This has the advantage that one can select a font big enough to compensate for the stretched dialog interface and at the same time it doesn't change the fonts in other parts of the UI that aren't able to handle big fonts.

Is there a way to achieve the same effect in BG2/Easytutu? fontdl1.bam respectively fontdlg.bam don't seem to do anything for BG2 and normal.bam replaces too much. Does anyone know a solution?

Solved
I found out that this mod for BG2 actually does the trick because it changes the game files (also by Ghostdog): http://www.shsforums.net/topic/52452-bigger-fonts-mod-for-baldurs-gate-2/
The font is a bit big, but you can simply replace it with another one, using the Font BAM Generator: http://www.shsforums.net/topic/41417-fonts-for-pt-pl/