Unfortunately Yoda, the sensor inside of a PnS digital is sealed behind the lens.
Another possibility, and just as bad, is that there is stuff in the interior elements of the lens, but this is less likely as I'd think that would have showed up from day one.
My guess is that OLY quality control missed this, and the offensive dust was in the camera from the beginning, and worked it's way onto the sensor.
If the camera is under warranty, then send it in to get it cleaned. This involves more than cleaning as they will have to take it apart to get to the sensor.
If the camera is NOT under warranty, I'd send OLY a copy of an image showing the problem, and suggest that this was a defect, and see if they will cover the costs. If you have to pay for this, it's going to run over $100, and likely double that or more.
Sorry dude, hope you can work this out with OLY. If OLY is uncorporative sometimes a gentle mention of potential negative publicity on a big photo forum like dpreview would help, but I'd save that as a last resort.