Soulskill from the new-and-improved,-now-with-larger-numbers dept.
scdeimos writes "Mozilla has announced the release of Thunderbird 5.0b1, the first in their new rapid release cycles. According to the Thunderbird Beta FAQ, Thunderbird 4 was skipped, as the program's version is now tied to the underlying Gecko engine."
We warn the reader in advance that the proof presented here depends on a
clever but highly unmotivated trick.
-- Howard Anton, "Elementary Linear Algebra"