I was pleasantly surprised to read today that the recent iPhone software update had added compatibility for some iPod accessories that didn't work before. In particular, my Belkin car charger/audio adapter now outputs sound to my car stereo as it should, and my Altec Lansing inMotion portable speakers now work as well (although for those I have to put the phone in airplane mode or the speakers crackle terribly). The only accessory that I have that still doesn't work is the iPod radio remote, and I'm afraid that might be a lost cause. In short, if you tried something earlier and it didn't work, it's worth trying again.