Created attachment 6731 [details] simple example of 2 download fonts Kens analysis: So the first string (in the lighter weight font) "Statement activity current as of August 19, 2010" gets encoded as you would expect. When we switch fonts, any text which is at a position which hasn't already been used gets encoded where you would expect, so *some* of the glyphs end up encoded normally. Glyphs whose encoding position has already been used get moved to the first empty slot. ... details elided ... Eventually, as we fill the font up with glyphs from numerous different input fonts, the output font becomes full and we start a new output font. I think this could lead to us loading the same characters into different fonts.
Addressed as far as possible in revision 11913: http://ghostscript.com/pipermail/gs-cvs/2010-November/011961.html