The famous George Hotz (aka GeoHot) has managed to do it again. If you have found yourself trapped with 1.1.3 out of the box on your new 8gb or 16gb iPhone and where hoping to unlock it, you’re in luck! After claiming that this feat would be impossible, GeoHot spent 24 hours to prove himself wrong and apparently he succeeded.
If you’re looking for a full guide to soft unlock your iPhone, you’ll want to either check out GeoHot’s Blog or the ModMyiFone Forums. Both include full detailed guides that will lead you through the process, making it very easy for you to accomplish this task. Although, just as both of those sites will tell you, you need to follow all of the directions completely or you may risk bricking your iPhone.
With the recent launch of the 16gb iPhone shipping out with 1.1.3 firmware, expect to see a slue of these things all over ebay, regardless of which countries are selling the it domestically.

[...] we showed you how GeoHot managed to unlock OTB iPhones running 1.1.2 or 1.1.3. Although the guide in there would allow anyone with time or [...]
[...] GeoHot Releases 1.1.2 / 1.1.3 Software Unlock [...]