You mean you have performed the lang. import in an other client than 000 ?
I always do it in client 000 as you often import lang. at installation time where 000 is the only available client. The 2 notes that did provides a procedure for lang. import (check attachment of note 1508122) do not talk about client 000.
So this might be a myth...
1508122 - Installation and troubleshooting of languages in SAP systems