Ok, I just confirmed this by attaching the file to this bug report and setting the mimetype to application/x-deb, and this works :)
** Changed in: firefox (Ubuntu) Milestone: ubuntu-11.04 => natty-updates -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/760644 Title: Default handler lookup by extension fails -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs