Quite a few Boiga species can be kept very much in the same way.
As B. tanahjampeana comes from the same reagion as the B. dendrophila gemmicincta you can care for them very much in the same way.
An ambient temperature of 27 degrees Celcius woth a coldspot a few degrees colder as well as a hot spot around 35 degrees celcius. Make good hidingplaces both high and low and provide misting daily. A humidity around 70% would probably be fine.
This is also how i care for my melanota and my nigriceps. The nigriceps are just misted more often 
Remember deworming if it's WC 
For more on WC care as well as general Boiga care you can check out the articles at
www.agkistrodon.homepage.dk
Link