Patent on streaming evaluation of XPath

[Christian Nentwich <christian@modeltwozero.com>]

Dear all,

I was browsing through the archives of xml-dev on optimised XPath 
evaluation, something I've looked at on and off since about 2000. By 
coincidence, I stumbled across this patent application for "optimised 
streaming evaluation of xml queries":

http://www.peertopatent.org/patent/20090125495/activity
http://www.freepatentsonline.com/y2009/0125495.html

Pretty cheeky. The first time we did something like that was around 
2001, when a student implemented it for me. I can probably dig up the 
report. STX and its Joost implementation (http://stx.sourceforge.net/), 
which was worked on in 2003, should also count as prior art. The only 
claim I cannot quite follow is the one on the "XPath engine sending 
instructions to the streaming component". If this is a material part of 
the patent, it may be a different claim.

This patent troubles me. It is sits squarely on a key requirement for 
high performance XML processing. I think it will trouble some of you, 
too. If anybody understands how prior art can be submitted for this 
(these pages are unclear about whether the patent is granted), I would 
very much like to hear from you, and so would the USPTO...

regards,

Christian