Drawing API - Draw rectangle by dragging mouse on canvas

[font=Georgia]I need to to incorporate a functionality where the user can use his mouse to draw a rectangle by dragging his mouse over the canvas - much like the Rectangle Drawing Tool in the Flash Authoring environment. The requirement is something like a rubberband tool where the user can define a portion of a map by drawing a rectangle over it. The coordinates needs to be captured. Can anyone help me with the actionscript.[/font]