[imp] undefined index errors imp/config/prefs.php

[John H. Bennett III]

Hello,

Whenever I go to horde to login and also when I logout, I am getting  
these errors in my log:

May 29 22:40:55 www httpd: PHP Notice:  Undefined index:  imp in  
/home/httpd/html/horde/imp/config/prefs.php on line 36
May 29 22:40:55 www httpd: PHP Notice:  Undefined index:  imp in  
/home/httpd/html/horde/imp/config/prefs.php on line 64
May 29 22:40:55 www httpd: PHP Notice:  Undefined index:  imp in  
/home/httpd/html/horde/imp/config/prefs.php on line 126
May 29 22:40:55 www httpd: PHP Notice:  Undefined index:  imp in  
/home/httpd/html/horde/imp/config/prefs.php on line 151
May 29 22:40:55 www httpd: PHP Notice:  Undefined index:  imp in  
/home/httpd/html/horde/imp/config/prefs.php on line 169
May 29 22:40:55 www httpd: PHP Notice:  Undefined index:  imp in  
/home/httpd/html/horde/imp/config/prefs.php on line 916
May 29 22:40:55 www httpd: PHP Notice:  Undefined index:  imp in  
/home/httpd/html/horde/imp/config/prefs.php on line 1421


All of these line numbers correspond with lines in prefs.php that begin with:
if ($_SESSION['imp']['base_protocol'] != 'pop3') {

What have I missed in not defining imp?  Note, I am currently using  
horde 3.2 RC4 and Imp 4.2 RC4 until I can find the time to upgrade to  
the released versions.

TIA,

John Bennett