dstiles - 8:58 pm on May 22, 2012 (gmt 0)
That specific IP had a go at my server a couple of days ago. It got rejected but tried 3 times in all.
All three hits were with the UA...
...same as a hit 15 minutes earlier from an AT&T IP (also blocked) and probably others.
I don't log POSTs in my security logs (they can be far too long!). The QUERYSTRING is the same though, but only on the second and third hits, not the first, which was probably just establishing contact.
I would guess it was trying to add something nsty into a php file on the site. Whether it could succeed depends on how you handle such things - or even whether your site is php in the first place. :)