[imp] dimp mailbox scrollbar in IE problem

[Nick]

Hi, I've downloaded DIMP 1.1 final and in IE7 the scrollbar does not work
correctly.
When it first loads, I see your css-styled scrollbar, and then a second
later a "system" scrollbar appears on the top of it.

this could be an overflow issue or with sizing?

If i resize the reading pane, then I can see correct dimp scrollbar, but
when clicking on it, IE's scrollbar takes over and effectively hampers my
scrolling.

any pointers as to what files to look at to fix it?