Fatal error: Call to a member function debug()

[Darus]

Joomla! 2.5.16 Stable
VM2.0.24a

I've had constant hassles with the ConvertECB.php. For some reason it is not writing the updated file, and after changing permission on the file, I started getting this message:

Fatal error: Call to a member function debug() on a non-object in /home/xxxx/public_html/administrator/components/com_virtuemart/plugins/currency_converter/convertECB.php on line 90

Any advice will be highly appreciated. Would updating to 24c have any effect on this issue?