> "One is that IBM is either a friend of open source, or it's simply an opportunist, supporting some projects when it suits, and attacking others when it doesn't."

Business exists to sieze opportunities. IBM is a friend to Open Source (eg, employing Linux kernel and Samba developers) when it helps sell mainframes and Power chips, but doesn't like emulators of it's proprietary mainframe firmwares. This sounds perfectly reasonable to me.

I suspect that the nastygram came from IBM's mainframe business unit, not one of the units which typically deals with Open Source.

TurboHercules should GPL their product & see what IBM does then...