plotting in R

Hi there, I have 2 questions which I cannot find answers for in Dalgaard 
or the helpfiles currently available.

(1) I wish to plot 3 ecdf plots on one graph.  Is there any way of 
holding a figure to plot all on the same plot.  I can't get an ecdf for 
any plot command other than "plot" or "ecdf.plot" so using lower level 
command is no good, have also tried x11().

(2) If I have three curves on a plot how can I label each curve so the 
label sits directly above the curve?

Thanks

Carla