Clever hardware buffs have found a pathway to enable VoIP calls on the newly released iPod Touch and Classic. Apple enabled the headphone jack to accept external microphones, with the intention of letting clients record voice memos on the devices. But with the right application, users could manipulate the external microphone capability to enable VoIP calls over WiFi through clients like Jajah and Skype.

Apple has yet to clarlify on its stance on VoIP calls over WiFi; the company expressly forbids VoIP calls using either the EDGE of 3G networks.                                                     

For more:
- see the blog post [1] on macrumors.com 

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