Vim syntax for .sig file?

I'm a unix guy for a living, and as part of that, I chose vi as my editor.

Now, I'm working on a couple Eventide related things, and one of them is adding an editor to vSigX. I've already played around with Scintilla, but since I'm partial to vi, I figured I might try to fit it in somehow. So the question for you guys is, does anyone have a vim syntax file for highlighting .sig files? (Anybody even know what that is?)   I figured I'd ask before starting one from scratch…