Wimax TLV definitions

Hello everyone. I have a question about TLV definitions on Freeradius dictionaries. From what i understand from the standard, the Type field for TLV can be up to two bytes. But when i tried to define a tlv bigger than 255 i get an error when Freeradius tries to read the dictionary: Errors reading dictionary: dict_init: /usr/share/freeradius/dictionary.wimax[190]: sub-tlv's cannot have value > 255 Is this a non supported length or am i misinterpreting the standard? if it is just unsupported, is there any plan to support tlv>255? Thanks