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Both can, although the feature that is being touted on the product pages is actually the MobileMe feature that is part of the new base stations and not the "share over WAN" feature that was already available on both older models. I have a first gen TC and I have the option to share my drive over WAN. I haven't done it yet, but I believe in order to access it abroad, you would need to connect via AFP (from a Mac) using your external IP address.

Edit: Here's where it's mentioned for the TC -
http://www.apple.com/ca/timecapsule/wireless.html
 
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