ORA-24801 when using Dataset.Fill

Question

I'm getting and exception ORA-24801 when I call the Dataset Fill method as per the following example.
The stored procedure takes 3 parameters. This error does not occur when calling another procedure which does not return CLOBs. Any ideas ??
oCommand.CommandText = "JBS_REPORT_002.Build";
oCommand.CommandType = CommandType.StoredProcedure;
OracleDataAdapter da = new OracleDataAdapter(oCommand);
OracleCommandBuilder builder = new OracleCommandBuilder(da);
DataSet ds = new DataSet();
da.Fill(ds);
Database is 8.1.7

Answer 1

Thanks for the reply.
firstly we have not tried on 9.2 and this is not an option.
Secondly the problem can be replicated without a stored procedure as per follows. If there is a CLOB field it fails.
string commandStr = "SELECT * FROM MYTABLE";
OracleDataAdapter adapter = new OracleDataAdapter (commandStr, conn);
try
OracleCommandBuilder builder = new OracleCommandBuilder(adapter);
DataSet ds = new DataSet();
adapter.Fill(ds,"MYTABLE");
catch(OracleException e){}