Have you taken a look at “Grant Skinner’s Janitor class”:http://www.gskinner.com ?
You can download it here: “Janitor class”:http://www.google.com/url?sa=t&source=web&ct=res&cd=3&url=http%3A%2F%2Fsvn.riaforge.org%2Fflexshell%2Ftrunk%2Fflexshell_extern%2Fsrc%2Fcom%2Fgskinner%2Futils%2FJanitor.as&ei=6Pj9SYe3Fp7qsgPu1MTJAQ&usg=AFQjCNFHh6pXVwWKoZhzwlq5Q2yg2aYdaA
If you’re using a loader, you should remove listeners and any other references, then use the unload() method.
“Unload method reference”:http://livedocs.adobe.com/flash/9.0/ActionScriptLangRefV3/flash/display/Loader.html#unload()