[imp] new language not being set on login

[amy.rich@tufts.edu]

We're using IMP authentication with horde 4.0.5 and imp 4.0.4.  When a user
selectes a new language (say Deutsch) from the login screen, it changes the
login screen to German.  The user types in his username and password and
clicks on login.  If the user had a previous language value stored in the
mysql back end, this value is used instead of what was selected on the login
screen.  If the user has not language preference set, then the one chosen at
the login screen is used (but not saved in mysql).

If the user changes the login languages after he is logged in, then the
preference is changed in the database.

It looks like loggin in with IMP authentication is just not saving the new
preference to the back end database.

Have other people seen this?  I checked the bugs database, and didn't see
any valid bugs that looked like they fit.