Since Function is just another type I was wondering. Is it possible to serialize functions in actionscript 3.0?
Do you mean to serialize not just the pointer to the function, but the actual function contents and then send them to a remote machine? I do not believe you can do that, you would have to use some type of remoting to do something like that.
With AS3, Adobe gave us enough power to create, modify and run ByteCode at run-time. You can achieve a 'function serialization' using this runtime bytecode concept.
This can get pretty technical, but I recommend you to read about some libraries that should help you:
I should also point that AS3Eval should be easier to understand -- swfassist have no english documentation, as far as I can tell. With AS3Eval you can modify code as a string and execute it at real-time, just like the old eval method.
Of course you can go hardcore style and implement a complex system on bytecode reading/serializing, but using such libraries would make it pretty simple.