after upgrading im having a problem with Site Cache

Drupal 5.0
Configuration file Protected
Cron maintenance tasks Last run 42 sec ago
You can run cron manually.
Database schema Up to date
File system Writable (public download method)
GD library bundled (2.0.28 compatible)
MySQL database 5.0.24
PHP 5.1.5
Unicode library PHP Mbstring Extension
Web server Apache/2.2.3 (Win32) PHP/5.1.6

When i enable cache i was always having problems, before It just use to get page can not be displayed (only when i log off and click on a link a second time. ) so i disabled it till i got the other modules working, And now its about that time... sessions-singlesignon- and multidomains seem to be working when cache is disabled but now instead of getting the error message "page can not be displayed" I get the following scripting error

Error:

Notice: Undefined index: HTTPS in C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\allensworld\modules\addmodules\multidomain\multidomain.module on line 277

Notice: Undefined index: http://www.allensworld.org in C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\allensworld\modules\addmodules\multidomain\multidomain.module on line 278

Notice: Undefined index: HTTPS in C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\allensworld\modules\addmodules\multidomain\multidomain.module on line 301

Fatal error: Call to undefined function t() in C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\allensworld\modules\addmodules\singlesignon\singlesignon.module on line 119

Notice: Undefined property: stdClass::$cache in C:\Program Files\Apache Software Foundation\Apache2.2\htdocs\allensworld\includes\session.inc on line 77

Can some one please help me.