Welcome Gil Levinson.
JSFL can only be used within the FLash IDE. JSFL commands cannot be excuted during run-time of an SWF.
the MMExecute command in actionscript can be used to run JSFL commands but are used only in swfs run in the IDE as a custom panel (WindowSWF), XMLtoUI, or timeline effect preview.
If you would like to use the dom's properties in your movie, you could run a command to fl.trace these in the output you prefer, and then copy that from the output panel and place it in your actionscript.
-hope it helps
** it's probably a type-o, but it is getDocumentDOM().