oracle 11g 透明网关连接mssql 2005报错？？？

通过oracle 11g 连接mssql 2005 报下面的错误
select * from maintanance@mssql
*
第 1 行出现错误:
ORA-28545: 连接代理时 Net8 诊断到错误
Unable to retrieve text of NETWORK/NCR message 65535
ORA-02063: 紧接着 2 lines (起自 MSSQL)
oracle 11g listener.ora配置如下：
# listener.ora Network Configuration File: D:\app\Administrator\product\11.1.0\db_1\network\admin\listener.ora
# Generated by Oracle configuration tools.
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME=UniteAlarm)
(ORACLE_HOME=D:\app\Administrator\product\11.1.0\db_1)
(ENVS=LD_LIBRARY_PATH=D:\app\Administrator\OraGtw11g_home1\dg4msql\driver\lib;D:\app\Administrator\product\11.1.0\db_1\LIB)
(PROGRAM=dg4msql)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = aRong)(PORT = 1521))
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
oracle 11g tnsnames.ora配置如下：
# tnsnames.ora Network Configuration File: D:\app\Administrator\product\11.1.0\db_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.
UniteAlarm =
   (DESCRIPTION =
     (ADDRESS_LIST =
       (ADDRESS = (PROTOCOL = TCP)(HOST= aRong)(PORT=1521))  
     )
     (CONNECT_DATA =
       (SID = UniteAlarm)
     )
     (HS=OK)
   )
其中，UniteAlarm是要连接的mssql的数据库，透明网关D:\app\Administrator\OraGtw11g_home1\dg4msql\admin下面的配置文件initUniteAlarm.ora如下：
# This is a customized agent init file that contains the HS parameters
# that are needed for the Database Gateway for Microsoft SQL Server
#
# HS init parameters
#
HS_FDS_CONNECT_INFO="SERVER=10.147.51.156;DATABASE=UniteAlarm"
HS_FDS_TRACE_LEVEL=OFF
HS_FDS_RECOVERY_ACCOUNT=RECOVER
HS_FDS_RECOVERY_PWD=RECOVER
请高手帮忙解决下，多谢！！！