Debian way to make tiny change to package

Have you ever had to make a one-line correction (or customization) in a big package? If so how did you manage it? The obvious way is to rebuild a package and serve it locally, but is there some other approach?
After spending an hour investigating bad behavior from the amoverview perl script in the amanda-server package (2.5.1p1-2.1), I traced the problem to one line in the script. It was an easy fix if you don't mind tweaking code directly in /usr/sbin/,read more...