The error is InvalidObjectException - Object with MOFID no longer exists. Run this SQL *twice in a row* to reproduce the error, which occurs on the DROP SCHEMA command.

!set force true
drop schema ddlgen cascade;

CREATE SCHEMA ddlgen;

SET SCHEMA 'ddlgen';

CREATE GLOBAL TEMPORARY TABLE ddlgen.temptab(x char(3) primary key)
DESCRIPTION 'a temp table'
ON COMMIT DELETE ROWS;

CREATE VIEW v
DESCRIPTION 'a view' AS
SELECT * FROM ddlgen.temptab WHERE x IS NOT NULL;

--
Here's a stack dump:

SEVERE: Object with MOFID j:00000000000038EC no longer exists.
Oct 3, 2007 6:19:02 PM FarragoJdbcUtil newSqlException(ex)
FINER: THROW
javax.jmi.reflect.InvalidObjectException: Object with MOFID j:00000000000038EC no longer exists.
        at org.netbeans.mdr.handlers.BaseObjectHandler._getDelegate(BaseObjectHandler.java:353)
        at org.netbeans.mdr.handlers.InstanceHandler.getInstanceDelegate(InstanceHandler.java:48)
        at org.netbeans.mdr.handlers.InstanceHandler._handleGetR(InstanceHandler.java:103)
        at net.sf.farrago.fem.med.FemLocalIndex$Impl.getSpannedClass(Unknown Source)
        at net.sf.farrago.catalog.FarragoCatalogUtil.getIndexTable(FarragoCatalogUtil.java:170)
        at net.sf.farrago.db.FarragoDbSessionIndexMap.onCommit(FarragoDbSessionIndexMap.java:189)
        at net.sf.farrago.db.FarragoDbSession.commitImpl(FarragoDbSession.java:732)
        at net.sf.farrago.db.FarragoDbSession.executeDdl(FarragoDbSession.java:1182)
        at net.sf.farrago.db.FarragoDbSession.prepareImpl(FarragoDbSession.java:1066)
        at net.sf.farrago.db.FarragoDbSession.prepare(FarragoDbSession.java:946)