TTL/WRITETIME function against collection column returns invalid value

Since we cannot query individual content of collection in 1.2, TTL/WRITETIME function on collection column does not make sense. But currently we can perform those function on collection and get deserialization error like:

value '\x00\x03\x00\x01c\x00\x01b\x00\x01a' (in col 'writetime(l)') can't be deserialized as bigint: unpack requires a string argument of length 8

Looks like it tries to deserialize whole list/set/map content as bigint for WRITETIME and int for TTL.