If your marriage has been registered with the National Registration Department (JPN) of Malaysia or the relevant Malaysian State Islamic Religious Department/State Islamic Religious Council or the relevant Malaysian Embassy/High Commission/Consulate-General abroad, you would be able to enter into Malaysia on an SVP. You can apply for a LTSVP upon entry into the country.
No matter what your permission letter says, make sure you receive at least a single-entry visa so that the airline can accept you on board.