Check out this page. The stuff is kind of pricey for what you want it for, I assume.
http://www.right-tool.com/doortools.html
I'd follow the outline with a new, sharp utility knife & chisel out the meat, as others have said.
If I was doing doors for a living those door tools would be right up my alley, otherwise thats a pretty cool site to look up tools. Thanks for the link. I order from
cumminstools.com or Harborfrieght at times. Now that Home Depot opened up two blocks away I'll have to control myself