Yep, As you say times have changed, I just do not understand why, If you have already stamped out of Thailand then why can you not use a different valid passport to stamp into another country ??
I am not talking about a visa run, I have never actually done one of those. I flew into Thailand and then exited through the border crossing into Malaysia on my way to Singapore. The reason I used both my passports was due to work visa's I had for malaysia at the time, were in a different passport than my Thai visa.
That is very interesting as I did this a couple of times when crossing from Thailand into Malaysia back in the 1980's with no problem at all. I had two UK passports. I guess from the comments here things have changed.
Jacob Lotsander They can do a search on name, birthdate and nationality, so technically they can connect you to a previous passport if you are using the same name.
Jacob Lotsander It depends on the country. ie In the US you cannot do this, the only way is to enter the country even if your final destination is outside the US.