Kaufman Bros analyst Shaw Wu has jumped into the iPhone rumour ring with reports that his supply chain and industry sources have spilled the beans on new iPhone models due to go into production.

Primarily he talks about the iPhone Sr, which boasts an improved battery life and a more powerful processor; and an iPhone Jr, which, as the name suggests, is less powerful and therefore presumably cheaper.

It seems highly unlikely that Apple will attempt to market two versions of the same device, with an underpowered unit selling at a lower price, of course.

If Wu’s sources prove accurate, what we’re probably looking at here is the new version of the iPhone for existing markets (being the Sr, which would pick up on the complaints over poor battery performance and a slower processor than the iPod touch 2G), while the so called Jr, model would likely be the reduced cost version for the BRIC markets.

Other rumours suggest that the production run will increase from 4.5 million units to nearer six million, while US operator AT&T is working on a new range of data plans.