When creating soucre code documentation with doxygen I see these annoying warnings, too: Pango-WARNING **: Error loading GPOS table 5503 they stem from graphviz dot tool. I am using debian testing with ii doxygen 1.5.5-2 ii graphviz 2.18-1+b2 ii libgraphviz4 2.18-1+b2 ii libpango1.0-0 1.20.2-2 ii ttf-freefont 20080323-3