Warn about the transparency group cases we don't support (non-normal blend mode, isolated, and knockout).
Warn about the transparency group cases we don't support (non-normal blend mode, isolated, and knockout).

darcs-hash:20090825225025-f546f-3e4f91b167b23902132326eb7ffdc1c0b796c5dd.gz

nqv/mupdf,nqv/mupdf,nqv/mupdf,nqv/mupdf,nqv/mupdf,nqv/mupdf