IMP problem

[David Uriot]

Hi!

I'm running RedHat 7.0 Linux with all official RedHat updates applied. I've downloaded and installed Horde 1.2.5 and IMP 2.2.5. Here's an overview of the other installed software which is necessairy for IMP to work.

apache-1.3.14-3
php-4.0.4pl1-3
imap-2000-3
kernel-2.2.19-7.0.1

I've configured phplib (which comes with Horde) to use shared memory to store sessions. Okay, IMP seems to work fine. I can log into IMP and I see my email. However, when I try to send an email, the following error appears in the 'Message Composing'-window:

Warning: Undefined index: Send Message in /home/shared/www/html/horde/imp/compose.php3 on line 251

I already tried to restart my Linux system, what goes wrong here??