Folks be very careful if you or anyone you know is travelling to Thailand - the new military government is cracking down on drugs big time, even doing random piss testing of Thais and foreigners alike. Jail time for THC in your system

The incident that I read about was in Pai, up north in the hills, but I've heard of it happening in Bangkok as well. Remember pot stays in your system for a long time (at least a month, maybe much longer), and the "it was in Holland, yer honour" defense doesn't work out there.
I love Thailand, but until they reverse this ridiculous policy, won't be spending my holiday money there again.
http://tinyurl.com/3yhtwm
NB "Farang"=foreigner, usually Western.