I think you are mistaken as to what is causing the problem. The name 'LINES' is a reserved token, hence it is not a valid identifier. For example if you try create table lines(line string) you will see the same error message. The request for a valid identifier by the parser is correct. I will look at adding a patch which outputs the token which is not a valid identifier if this case so that when a reserved word is used it is clearer.
I could be wrong this is my first time digging through the hive code.