As indicated in my answer to your other question, when upgrading you have to ensure that all products, add-on's and custom implementations are upgraded to match the new version.
In the case of an upgrade from 2009 to 2011 (which you have done), on the Content Delivery side there has been a change in the API for the logging framework. This means that all code which was using the logging framework needs to be revised.
If it is a SDL product, then there should be a newer version available for that, if it is a SDL add-on product, the same story applies, and you should be able to find a newer release of that add-on product available (contact Customer Support for details o how to obtain it).
However if it is an unsupported "product" (sometimes these are referred to as packaged service) or just part of the implementation, you will have to revise the code yourself. You should of course contact the people who originally created that in case you didn't write the code yourself, and ask them to revise it to match the new API/framework of your upgraded version.