I'm sorry for not explaining where to find it, you have to do show application contents on the application (right/ctrl click) to do it in finder or it's in /Applications/PS3\ Media\ Server.app/Contents/Resources/Java/ which is kind of the default 'current directory' for OS X Java Apps.
I have noticed a quirk or two though. I'm not sure if it appears in other versions, as I've only tried the OSX version. When you approach the end of a tsMuxeR file, the playback becomes jittery and starts replaying old clips from earlier, rather than just ending as expected. I think it's seeking further and further back in the file (due to -ve arguments to seek_set?) buffer usage goes negative too.
Also rewind doesn't work very well in general, and fast forward is not as good as when using mencoder. The benefit of virtually 0 cpu load is well worth the loss of seek functionality tho!