Package: libc6-dev Version: 2.1.1-12 mntent.h should have, at least, MNTTYPE_PROC and MNTTYPE_AUTO, in addition to the ones there (it may be missing more, but those were the obvious ones.) The lack of MNTTYPE_PROC causes a bug in mtools (mzip -w fails trying to stat "proc" - it *has* code to check for MNTTYPE_PROC, but the define isn't there.)