OFlash uses the media player Flash file from Jeroen Wijering's FLV Media Player. JW FLV Media Player uses the Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported license. This makes it free for non-commerical use under the terms of the license. If your wiki is commercial, you probably need to buy a commercial license from Jeroen Wijering.
Orifice Software | Fergal Hainey