OpenX: Passing parameters to HTML creative from website

I'm trying to find a way to pass parameters from a website to a HTML creative being served via OpenX. For example, I want to add a parameter foo=bar to the invocation code, so that this would be available in t开发者_开发问答he creative somehow.

Is there a way to achieve this in OpenX? I'm a total newbie to it and RTFM and Googling the matter yielded no results.

Answering my own question: http://www.openxconsultant.com/blog/2010/12/how-to-dynamically-insert-an-affiliate-id-into-a-banner/

So, oops, wasn't a programmin related question after all (I assumed that this would've required OpenX hacking). Sorry :P

It is so simple to ad a custom limitation in invocation code you just have to pass a key=value pair in URL, which Javascript code is generating for accessing the banner, then you can set limitation on your variable's value.