For the record, Samb ended up talking it out with his DM, and showed him the thread on the OoTS forum. The end result was that the psionic rogue was still out of play, but Samb was permitted to play SRD psionic characters so he got to work on a psychic warrior. Apparently the whole thing started largely because the DM was feeling overwhelmed trying to track multiple abilities, effects and power points and whatnot from the various non-core classes, including the party swordsage.
Frankly, I think the DM was over-reacting, but I've been that kind of DM before, so I understand the stress he's under. When you don't really understand what a character is capable of and don't know how to challenge it, DMing can get overwhelming sometimes, and that's not much fun. I've banned crap that I shouldn't have, and I've also allowed stuff that I should have known better than allowing. Thankfully, my PCs were all mature enough to build a bridge and get over it, as they say.
As a PC, I've had it happen to me as well. My whisper gnome got house-ruled to normal gnome, my swift-hunter got Spell Compendium spells banned, etc. But I never considered ruining the game as some sort of "fair payback."
Kell's approach seriously repels me, and that's putting it lightly. It's not the DM's job to provide entertainment - people DM because they want to have fun, just like you. If he changes the rules of the game mid-way and makes it core-only, then the responsible thing to do is state your piece. If you seriously can't enjoy a core-only game, then I would just walk away, not act passive-aggressive and ruin the game for the DM and the other PCs.
Honestly, I don't see how it achieves anything in the end. You walk off in an angry huff, the DM retcons the evening and says "So the mad wizard's planar bomb was merely a bad dream!" and the game goes on, only now you're off looking for another group, and your old group had to put up with a night of angry D&D, which nobody enjoys.
And I don't mean this post as a personal attack, Kell - it's just that I can't understand how you can justify that kind of behavior, especially multiple times. Char op gets a bad rep from exactly this sort of thing, and it frustrates me sometimes.