Restoring AppleScript for Signatures

Since the initial release of Mac OS X 10.4 "Tiger," Apple's own mail client has had a bug that annoyed me to no end. Under Panther, it was possible to set the text of email signatures via AppleScript. I used this capability to build a number of scripts to add Fortune quotes, system uptime, and assorted quips about the superiority of Mac OS X in general, all dynamically rotated on a scheduled basis. Every email I sent had a new quote and an up-to-the-minute report on my system's uptime. Geeky, but then I'm easily entertained...
Unfortunately starting with Tiger, this functionality was broken. The necessary methods are still exposed in Mail's AppleScript dictionary, but they simply don't work. Calling them results in an error message in the Console log and nothing more. At the time of this writing, Apple has released five updates to Tiger and a few assorted security patches along the way. Still, the underlying bug that prevents dynamically updated signatures had not yet been fixed.
Fortunately, through the magic of mailbundle's, Apple's bug can be patched even if Apple hasn't the inclination to do so.
A Trac installation with Wiki and bug tracker for DynSigFix can be found here.