Problem with the multiline

programming flash
1

I have problem with the **multiline. **The problem is that I have put **multiline **to **true, **but the text is still on one line?
Please help me!!!

_root.createTextField("start_txt",300,300,50,400,200);
 start_txt.text = start_info;
 start_txt.border = true;
 myStart = new TextFormat();
 myStart.color = 0xFFFFFF;
 myStart.font = "arial";
 **myStart.multiline = true;
** myStart.type = "dynamic";
 start_txt.setTextFormat(myStart);