I have two forms not displaying properly in IE7. in IE dev tool bar the div wrapper for the form has some odd attributes such as sizset and sizecache, but one weird attribute is h and h was set to some height. as soon as I deleted that 'h' attribute (in the dev tools) the form height was recognized and layout worked.
Here is an example where the form is in a post > http://heartoftexasgreenexpo.org/category/contact/contact-summary
A clearer example in a page is here (password= expo) > http://heartoftexasgreenexpo.org/application-for-exhibitor-vendor-space
Obviously you can't see the error without IE7. I only have IE7 as a test platform for some in-house apps and that is how I caught the problem. The form looks great in other browsers and IEs.