Why has no one suggested to check the PCV system? Check your PCV valve and the vent to make sure they are not plugged. Too much crankcase pressure will force oil out of bolt holes around oil pans, valve covers and intakes. If you a running at high RPM's most of the time you may need a vacu-pan system as the PCV system becomes ineffective at low vacuum conditions.

I know this is an old thread but it seemed the obvious was missed. This may help someone in the future.