Hibernate + Derby - Unable to determine stream header for hibernate type 'text'

Hello all,
We have just started to look into Derby as our embedded DB for a desktop app version.

Env: Hibernate 3.2 and Derby 10.5.1

I have defined a java string field of type 'text' in Hibernate Mapping (works great on Postgres 8.1 and Oracle 10g), and Hibernate's DerbyDialect generates a CLOB (255) column for that field in Derby

I use Hibernate SessionFactory to generate Table schema, which is done without any error.

But, when I try to save records in tables via Hibernate Session, I get the following exception:
Note: If I change hibernate mapping to type 'string', then I dont get this error:

java.lang.IllegalStateException: No context, unable to determine which stream header format to generate
        at org.apache.derby.iapi.types.ClobStreamHeaderGenerator.determineMode(Unknown Source)
        at org.apache.derby.iapi.types.ClobStreamHeaderGenerator.expectsCharCount(Unknown Source)
        at org.apache.derby.iapi.types.ReaderToUTF8Stream.fillBuffer(Unknown Source)
        at org.apache.derby.iapi.types.ReaderToUTF8Stream.read(Unknown Source)
        at java.io.DataInputStream.read(Unknown Source)
        at org.apache.derby.iapi.types.SQLClob.readExternal(Unknown Source)
        at org.apache.derby.iapi.types.SQLChar.getString(Unknown Source)
        at org.apache.derby.iapi.types.SQLClob.getClone(Unknown Source)
        at org.apache.derby.impl.sql.GenericParameter.getClone(Unknown Source)
        at org.apache.derby.impl.sql.GenericParameterValueSet.<init>(Unknown Source)
        at org.apache.derby.impl.sql.GenericParameterValueSet.getClone(Unknown Source)
        at org.apache.derby.impl.jdbc.EmbedPreparedStatement.addBatch(Unknown Source)
        at org.hibernate.jdbc.BatchingBatcher.addToBatch(BatchingBatcher.java:31)
        at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2252)
        at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2665)

Also, I need to save it as type 'text' even though it gets saved as CLOB(255), as the CLOB column size can later be altered.

What could be the cause? or changes needed?

thanks all