[flexcoders] lineTo to a point off of the chart makes the whole line disapear?

[tudsy]

I need to be able to draw lines on a chart in data coordinates and
have them extend to the edge of the chart.  The boundaries of the
chart change dynamically between about (-20,20).  

So I'd like to just use moveTo and lineTo to draw lines between
distant points and have the appropriate segment of the line between
the current bounds be displayed automatically.  However, using lineTo
to a point not on the chart doesn't seem to draw any line.

Any tips?