Nunit stops on Log entry.

Question

Hi,
I've created an nunit for my dlls to test. But the problem is, nunit stops at log entry of my dlls code when I try to debug my nunit code.
It will generate an error when tried to run the test, it says "System.NullReferenceException: Object reference not set to an instance of an object.." and when I tried to comment out the log entry(Logger.log("...")) inside my dlls method it will run as expected.

Please advice.

thanks in advance,
gilmar