ABOVE: A Micro-SIMM for a 3G iPad sold by US carrier AT&T. The new format - 52% smaller than the Sim cards used in all New Zealand phones and mobile data devices today - will also be used in Apple's coming fourth-generation iPhone. That will hamper Telecom, as its SIM cards would no longer simply slot into Apple's handset.

The 3G version of Apple’s iPad went on sale in the US over the weekend and proved another blockbuster.

According to retail checks by analyst Piper Jaffray, 300,000 units of the 3G iPad were sold over Saturday and Sunday.

That is, the same number as the wi-fi version of the iPad launched last month, despite the 3G + wi-fi version ($US629 to $829) being more expensive than the wi-fi version  ($US499 to $699) across most memory options.

Apple has now sold more than one million iPads in 28 days, according to Apple's figures, helping the company's shares (NAS: AAPL) rise more than 2% today as the US market reopens (they’ve now doubled in the past 12 months).

The iPad 3G will go on sale in large parts of Europe and Australia later this month, sold through Vodafone.

New Zealand - still waiting for the plain-vanilla wi-fi version, doesn’t make the 3G cut either and there’s no release date in sight.

Little SIM, big problem for wannabe importers
Worse, although enterprising Kiwis - from the likes of Wellington’s Quay Computers to toshnewzealand.com to a rash of entrepreneurial types on TradeMe - have been able to parallel import the wi-fi iPad, the 3G version will be trickier to grey market.

Activating a parallel imported cellular device without Telecom or Vodafone’s official approval is nothing new. The sometimes troubled Parallel Imported, and others, have been doing it for years. You pop your existing SIM card (used to identify your account, and to hold other information such as numbers) from your existing phone into your parallel imported phone, get the guy in the shop to execute a couple of settings tweaks (or do it yourself) and you’re away laughing).

But the iPad’s twist is that it requires a special format SIM card called a micro-SIM, which is 52% smaller than a regular SIM card.

Micro-SIMS are unknown in the New Zealand mobile device world  (a spokesman for Vodafone said Micro-SIMs do already feature in various embedded devices in NZ, including power meters and burglar alarms, but not yet cellphones. Long term, Micro-SIMs are expected to become the standard for all cellphone makers.)

The new SIM format took the technology world by surprise, but the extra control afforded by its relatively unique design suits Steve Jobs' carefully time-lined plans for world domination.

New SIM format a complication for Telecom
If an Apple prototype secured by gadget site Gizmodo is anything to go by, the fourth-generation of Apple's iPhone will also feature a Micro-SIM.

If it is released with the new-format SIM, it would complicate Telecom's efforts to grey market the Apple handset.

Of course, Telecom could always become an official Apple carrier by the time the 4G iPhone launches, which would make life easier for almost everybody ...