[GRASSLIST:3987] Geo referencing jpg image for digitizin.

Hi Folks,

I know someone answered this before, but I can't find the e-mail where I 
had the directions.  I want to scan a map and use the image to trace 
contours.  I need to know how to geo refrence the map so the image's 
corners match there location on the Irish National Grid.

Thanks for your help.

Kurt