I am using Logitech Wireless Headset on my iPod device. I have no problem with it on any other VOIP (Bobsled, MobileVOIP, Textfree and etc.) except Skype.
The problem with Skype is it is not routing the connection to my Wirelss Headset, and it always end up with playing on the open speaker and the mic on the iPod Touch.
I'm having the same problem, and the Logitech wireless bluetooth headset is still working with everything else, even with skype for the dialtone, but when the call is connected it switches to the speakerphone on the ipod 4Gs