It looks like the Japanese carrier NTT DoCoMo may have managed to convince Research In Motion to include support for quad-band 3G in the Japanese version of the Bold. Then again, it may all be a misunderstanding due to conflicting information.
The BlackBerry Bold page on the NTT DoCoMo site showed “FOMA Plus Area”, suggesting that the Bold covered not only the 850, 1900 and 2100MHz bands we expected but also the 800MHz band used in some rural areas of Japan. Interestingly, the Japanese RIM specification sheet indicates that FOMA Plus Area (800 MHz) is not available. So, does the Japanese Bold claim bragging rights as the first quad-band 3G device or not? Granted, I am relying on Google translations of both pages so something could have gotten lost in the translation.
The point may be moot as DoCoMo has pulled the BlackBerry Bold due to overheating issues while charging. RIM has confirmed the issue and has indicated that it is limited to the Japanese Bolds which had only gone on sale last week.
Source: The Boy Genius