Error On Install

Hi All,
Just trying to install, and having some problems.

After going through the install pages, everything checks out fine and proceeds...

After hitting the install button after the Installation summary page (all OK) I get the following message...

Fatal error: Class ’modUser’ not found in /home/rbmassag/public_html/core/model/modx/mysql/moduser.class.php on line 7

Really dont know what to do here.. have done about 8 installs with modx previously, and havent had a problem like this...

Any help would be appreciated!

Details:
Modx 2.1.2-pl - Traditional
Apache version 2.2.17
PHP version 5.2.14
MySQL version 5.0.92-community
Architecture x86_64
Operating system linux

Using Chrome....