The chipset (msm7200) for the Kaiser does not support Japanese bands. Qualcomm made a statement in June O6 that the chipset of the Kaiser has support of AWS.

http://www.cdmatech.com/download_library/pdf/msm7200_chipset.pdf
http://www.qualcomm.com/press/releases/2006/060628_adds_aws_band.html

Kaiser does support T-Mobile AWS and will be released soon for T-Mobile.

If it says 1700 MHz for Japan, it’s different than T-Mobile’s 1700 MHz AWS. T-Mobile AWS uses Band IV (1710-1755 MHz UL, 2110-2155 MHz DL) while Japanese Band IX is (1749.9-1784.9 MHz UL, 1844.9-1879.9 MHz DL).