HDR strange color artifacts

I have just tried HDR on some waterfall photos. It seemed quite helpful as a possible alternative to opening at different exposures in RAW. HOWEVER, some very strange multicolored objects appeared hidden in various places throughout the image, making it completely unusable. I am glad to email a sample comparative to a TIFF from the same session. Anyone care to help?

You can post a sample here via <http://www.pixentral.com/>. file size needs to stay below 2mb though.