I have the same problem in AMD64 Dapper. Launch firefox from a terminal and you will see the following when djvulibre fails:
LoadPlugin: failed to initialize shared library /usr/lib/netscape /plugins-libc6/nsdejavu.so [/usr/lib/netscape/plugins-libc6/nsdejavu.so: undefined symbol: XtShellStrings] -- Djvulibre Plugin https://launchpad.net/bugs/68766 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
