iPad 3G is SIM-locked to Softbank Mobile network in Japan

Apple confirmed on Monday to IDG News Service that the iPad will ship locked in Japan. That's a change from January, when the iPad was first unveiled and Apple co-founder Steve Jobs said that the device would be unlocked internationally, allowing customers to choose their carrier.

"All Japanese models will be SIM-locked to Softbank Mobile, Apple's iPhone partner in Japan, Apple said late Monday," the report said. "The company confirmed the presence of a SIM lock but couldn't immediately explain why it was enforcing the restriction in Japan."

The report noted that SIM locking is common in Japan, where unlocking is not offered by network operators. It also said the iPad price is comparable with other countries, suggesting the price of the touchscreen device is not subsidized by Softbank in Japan.

Japan is one of nine countries that will receive the iPad — both the Wi-Fi -only and 3G-capable models — on May 28. Apple has just begun accepting preorders. As with the U.S. launch, preorders of the iPad are limited to two per customer.

The iPad uses a micro-SIM card measuring 12mm x 15mm, which is under half the size of a standard SIM card as found in the iPhone 3GS. It is possible to cut down a full-size SIM card to turn it into a micro-SIM.

In the U.S., iPad data plans are available through AT&T, at $15 per month for 250MB of data, and $30 per month for unlimited access. Though the device is unlocked stateside, the iPad's internal 3G radios are only compatible with AT&T's high-speed data network in the U.S., leaving customers who wish to use the device on T-Mobile's network relegated to slower EDGE speeds.