In-Post Ads and Openx

I tried to put open-x javascript code which displays adsense ads into the in-post ads plug-in. It accepted the ad (I copied the code in html view and turned off the title display), but when the adsense code was created, it replaced the whole page. The whole page loaded, then the ad was created (which was contextually correct), and then the page was replaced with the ad.

Any ideas?

Thanks,

Andrew