2011.06.15 15:49 "Re: [Tiff] bug in G4 encoder.", by Lee Howard
I actually used the libtiff 3.9.5 in Fedora 14 when I got good results.
I'm using libtiff straight from source without distribution patches.
Perhaps it has been patched in some way. There was breakage of the G4 codec a while ago, when a fix to stop a potential buffer overflow screwed up some images. Is this the same issue resurfacing?
If anything like that, then, his Debian distro is breaking it by patching it.