IMP logs me out immediately

[Scott Toderash]

I am setting up IMP for the first time, and I got it installed from
RPM's.  It is (nearly) working.  I read this part of the FAQ:

5.3.9 IMP logs me out for no apparent reason at all.

The symptoms sound exactly like what is happening - I can login, see the
contents of my inbox, but as soon as I click on anything (preferences,
for example) I am asked to log in again.

The answer in the FAQ says that the problem is with my php.ini file,
which may be true but.... It says to use php.ini.dist which I don't
have.  What part of php.ini should I change to fix this problem??

Any help would be appreciated.

thanks...st

Scott Toderash
Rainy Day Software Corp.

ps.

brand new install of RH 7.1 with:
php-4.0.3pl1-1
imp-2.2.6-1rh7
horde-1.2.6-1rh7
apache-1.3.14-3