How to reach the maintimeline?

Hi

I have a project where I have attached i class to a movieclip I want to send a variable from the class to the maintimeline. I have done this in a project whith a document class then I used a function in the maintimeline and caled this from my class like: this.myfunctionintimeline(thevirabletosend);
but how do a acheaved the same in this case?