I ve been in KLIA twice (last time 2 years ago).Immigration checks carried out thoroughly (even when they noticed the official invitation from MAS for assessment ) as well as the security checks on my flights back to Europe ( 2 points of security,first after the immigration and the second right on the boarding gate,where i forced to leave two bottles of water,as i didnt expect second security check). So i am bit surprised about concerns for the security in KLIA. As far as it goes for the passport issue ,one of them was not on the INTERPOL missing list but still no clue what went wrong with the other one,especially on a flight bound to China where visa restrictions are quite strict .