Msg#: 4469323 posted 1:20 pm on Jun 26, 2012 (gmt 0)
In case anyone is following this or finds it via search, here's a critical update:
jQuery .post() DOES accept relative paths; what happened in my case is that, for general website security, I added an .htaccess file with "deny from all" to a directory that contained my php script. Since jQuery .post() requests the page via HTTP, my .htaccess denied it.
So if you're sure your code is right but get no result, that may be why.