[TYPO3-english] div2007 extension upgrade problem

[PIT Solutions]

Hi All,

I've a typo3 version 4.7.17 and a div2007 extension version 0.14.1.
I want to upgrade this extension to the current version 1.1.2.
But when I upgrade I got an error like this;

Fatal Error: Class 'tx_div2007_core' not found in /typo3conf/ext/div2007/class.tx_div2007_alpha_language_base.php on line 80

New div2007 extension contains 'tx_div2007_core' class, but I don't know why this error happend.

Please help me if somebody face this problem before.

Thanks & Regards,
Arun Chandran