A bit of a late reply, but you may find xmlBlaster worth a look - it seems to be in the rough ballpark, speed-wise (672 messages/s in 'acknowledge each message' mode, a couple of thousand/s in bulk mode) and has bindings for multiple languages ("PHP, Perl, Python, C, C++, C#, Visual Basic.net, Flash, J2ME, Java client samples are delivered in the xmlBlaster distribution.").

I've no idea how good it may prove - it's in my "could come in handy at some point" list - hope that helps.