OM-D - Waterproof?

No. Weatherproof...big difference. Or is it?

I'm just back from a week in northern NSW and spent some time on a property near the Border Ranges. While scooting around on a ATV I hit a sink hole in a paddock and watched my OMD shoot off the front tray and sink into about a foot of mud and water...and it was on.

I dried it out and turned it off. Next day it would turn on...and then off. Sometimes it would stay on but do odd things, like tell me the card was write protected (it wasn't) or not allow me to access the menu, or randomly delete when scrolling, etc.

Day by day it has slowly righted itself (I'm assuming as the interior moisture dries out) and now it appears to be functioning pretty much as normal (more than I can say for the 14mm pani that was on it at the time - very rough now).

Question is, should I now assume that all is well or should I suffer the temporary loss of the camera while Olympus give it a going over? Will the circuit board now slowly rust away?

Anyone had any experience with dam-dunked digital "weatherproof" cameras?