Kind of thread and Inheritance

Hello!

I would like to know if there is somekind of thread in as3 (flash is single-threaded right?), because I am using the GIFPlayer class from bytearray, and when it loads larger gifs, it makes my game hang! What should I do?

About the Inheritance, if I override a function from the father class, is there anyway to call the father function (like you can in C++)?
EX:

//father class
protected function something():void { … }

//child class
protected override function something():void
{
call father something();
do others stuff…
}

Thank you!