WLS Truncating empty schema definitions from soap query

Hi.

We have a problem with schema definition on WLS.
when we declare <SearchData xmlns=""> in outgoing soap message, it is logged in debugging, where it is shows as is.
But when the message reaches the endpoint, the declaration is missing. The endpoint receives the element as <SearchData>
Is this something that WLS configuration can do, remove the empty declaration? How do we fix the problem?
This is a simple reference to the root schema, and because xmlns="" is removed, this message ends in soap validation error.