Enabling class loader debugging helped,
In configuration/config.ini add the following property
osgi.debug=configuration/equinox-debug.properties
In configuration/equinox-debug.properties add the following properties,
org.eclipse.osgi/debug=true
org.eclipse.osgi/debug/loader=true
Now when you restart the container it prints out the BundleClassLoader which is attempting to load your class. I wanted my bundle to a be added as a fragment to the bundle which was loading this class, so once I figured out which bundle was loading the class I simply used that as the fragment host.