SUPBigString not updating in backend DB

Hi

We are facing a problem with using SUPBigString as datatype in Mobile Business object. Our backend DB is a MySQL DB and the attribute which I'm talking about is of type "text" which mapped to "bigString" on SUP server. We could successfully read the string from the mobile device but the problem is that when we update this attribute locally on the device and make a synchronization to update the backend DB, only this attribute is not updated in the Backend DB while all other attributes are updated during the update operation.

Thank you,

Amr