By mistake, added my answer as a comment.  Re-edited and modified with new information and moved to Answer. <br/>
There is nothing special about a normal power strip with three prongs. A probable cause of why your power strip was arcing in the outlet is either the power strip or outlet was damage.  With new information from OP, the outlet was damage when "bumped" and now has an internal short. The short involves the ground (round) prong).<br/>You are right to not use that outlet and until it is replaced. Also I would throw away the power strip that was arcing.