呼叫中的号码或参数类型错误

我已经成功创建了一个包。但是当我尝试在c#程序中调用它时我得到一个错误:调用LOG_STATUS时参数的数量或类型错误

LOG_STATUS是过程的名称:

CREATE OR REPLACE PACKAGE BODY ITMON.SERVERSTATUS AS  
PROCEDURE LOG_STATUS(out_RESULT OUT sys_refcursor)   
IS 
BEGIN
OPEN out_RESULT FOR
    SELECT HOSTNAME, USERS, PS_NAME 
    FROM PS_COLLECT
    WHERE NOT EXISTS
( 
        SELECT HOSTNAME, USERS, PS_NAME
        FROM PS_MASTER
        WHERE PS_MASTER.HOSTNAME = PS_COLLECT.HOSTNAME 
        AND PS_MASTER.USERS = PS_COLLECT.USERS 
        AND PS_MASTER.PS_NAME = PS_COLLECT.PS_NAME
    );
 END LOG_STATUS;  
END;

这是我的c#代码:

            OracleCommand OCom = new OracleCommand("SERVERSTATUS.LOG_STATUS", oc);
            OCom.CommandType = CommandType.StoredProcedure;
            OCom.Parameters.Add("out_RESULT", OracleType.VarChar, 30000).Direction = ParameterDirection.Output;
            OCom.Parameters[0].Value = sid;
            OracleDataAdapter _daGrid1 = new OracleDataAdapter(OCom);
            _daGrid1.Fill(_dsGrid);

OCom.Parameters.Add("out_RESULT", OracleType.VarChar, 30000).Direction = ParameterDirection.Output;

OCom.Parameters.Add("out_RESULT", OracleType.Cursor).Direction = ParameterDirection.Output;