Actually, it's quite common to force the users to log back in after changing passwords. It helps ensure that they changed it properly, and it allows them to actually use the password once while it's still fresh in their minds, so it builds a mental reminder.
Sometimes the only way things ever got fixed is because people became uncomfortable.
For my next feat, I will require a volunteer from the audience! Perhaps this tiny ad?
Free, earth friendly heat - from the CodeRanch trailboss