curveTo for graphing

Ran into a few problems with the curveTo action-script.

I was plotting a graph using lines like:

_root.clear();
_root.lineStyle(0, 0x00ffff, 100);
lineTo(100, 100);
lineTo(200, 80);
lineTo(300, 100);
lineTo(400, 200);
lineTo(500, 250);
lineTo(600, 300);

Now I'm looking for a function using curveTo to draw this graph curved.

Thanks in advanced for any help.