Hmmm, Strange place for a crack to show up unless it got wacked on the road or sump'n. When you say "side", are you talking about under the push rod tube area or between the engine case and tranny? Which side?
Driver side, pass. side ? These leaks can be like leaks in your roof. They start in a one place and show up 10' away. After you clean it off,how long does it take to show up again ? Worse hot or cold ?
Without looking at it in the flesh its hard to say.