[Enigmail] Enigmail on Ubuntu 9.04

[Robert J. Hansen]

Since upgrading to Ubuntu 9.04, I've discovered a weird behavior:
despite having my passphrase cache set to a nice high value, Enigmail
refuses to cache my passphrase for any length of time.  Each and every
encrypted email I receive requires me to re-enter a passphrase all over
again.

This occurs using official Ubuntu packages.

Anyone know what's going on?