If a branch refuses to open it to you, just try another branch. It really depends on the person you're talking to. I've opened mine with Bangkok bank. Just needed a Thai citizen with me to sign as my guarantor. I was on a tourist visa at the time.
Richard Swire I arrived in the end of November with a non-b valid until the end of Feb (3 months length) and a wp3 which has not been canceled or covered into a work permit.