[TYPO3-english] Class not found - 4.3.1 install problem

[Bertalan Fodor (LilyPondTool)]

Hi,

I've got several Typo3 4.1 and 4.2 installations running.

Now I started a new site running Typo3 4.3. After successful 
installation of several extensions, I'm unable to create the Hello world 
page using the automaketemplate extension.

I get the following when opening the frontend.

Class 'tx_automaketemplate_pi1' not found 
in */home/t3site/typo3_src-4.3.1/t3lib/class.t3lib_div.php* on line *4942

*The backend works without any problems, the extension manager doesn't 
report any problems when opening the settings page of the installed and 
enabled automaketemplate extension.
*
*Could you give me any advice what to check?

Thank you,

Bert