Just a datapoint, but my recent experience seems to suggest that the official line when you call MH is quite a bit more rigid than when you just show up at the airport. I bought a ticket for my friend in KL (KUL-LHR) through Expedia (to avoid credit card issues) and about 3 days before the flight we noticed that the name on his ticket was.... well not sure how to describe it... he has a Muslim name with about 8 names and Expedia jammed all of them together into the last name field with no spaces between any of the names. After a brief panic we decided that going through all the grief between Expedia and MH getting the ticket reissued wasn't worth it and we would take our chances. He did show up a couple hours early just in case there was a problem, but the MH check in gave him his boarding pass no questions asked. Same result on the return from LHR.