For those of you who can understand this kind of stuff and don't wish to speculate
a quick Google search revealed HKT's navigational specs at this address:
http://www.aviation.go.th/technical/nav/phuket.htm
Interesting to note that in true Thai style, a surreptitious public blame game has already started in the Thai media...
"Probe Looks At Human Error"
http://www.nationmultimedia.com/2007...s_30049332.php
Notwithstanding, I live in hope and wish for the best for everyone affected. My deepest sympathy.