Can't put img into excerpt / teaser

Issue Summary

I've installed the Excerpt.module, and it works beautifully with everything (so far) except bookreview & moviereview. I want to customize the code in the teaser so I put a thumbnail picture of the book cover there. Unfortunately, when ever I put img code into the excerpt, it strips it out. This happens no matter what kind of input I select: filtered, full html or php code.

Alternatively, it would be cool if we could set the url to a thumbnailed version of the cover, and it would insert itself automatically into the teaser.