This is a issue, when creating advanced administration intefaces for custom modules, since all modern jQuery plugins and CSS is based on modern rendering.
This is "only" a problem in IE9, sinces it forces the child page to the same DOCTYPE as the parent page. And since custom administration modules are loaded i an iframe and the parent page is in quirks-mode, the custom module administration will always run quirks-mode, then the the browser is IE9. :(
It would be nice to get rid of Quirks-mode, in Dynamicweb administration.
Best regards
Caper Stendal