There are a few places in MediaWiki that assume that JS/CSS are only stored in the MediaWiki namespace or in User subpages; basically anything that calls Title::isCssOrJsPage() or isCssJsSubpage().
This isn't a very good assumption, and with the introduction of Gadgets 2.0 and the Gadgets namespace, this will be false.
Version: 1.24rc
Severity: normal