If I connect through CMAN , same error is coming. Now I am giving U details of
architecture. I have one machine HOSPNT(192.9.200.1) and another machine
DEBA(192.9.200.2). Now listener and CMAN are running on HOSPNT.

The configuration of Listener.ora( on HOSPNT)
---------------------------------------------
# LISTENER.ORA Network Configuration File: E:\ORANT\network\admin\listener.ora
# Generated by Oracle configuration tools.

LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = hospnt)(PORT = 1521))
)
)
(DESCRIPTION =
(PROTOCOL_STACK =
(PRESENTATION = GIOP)
(SESSION = RAW)
)
(ADDRESS = (PROTOCOL = TCP)(HOST = hospnt)(PORT = 2481))
)
)

SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = E:\ORANT)
(PROGRAM = extproc)
)
(SID_DESC =
(GLOBAL_DBNAME = edp)
(ORACLE_HOME = E:\ORANT)
(SID_NAME = edp)
)
)

The configuration of CMAN( on HOSPNT)
-------------------------------------

cman = (address_list=
(address = (protocol=tcp)(host=HOSPNT)(port=1610))
)

cman_profile = (parameter_list=
(maximum_relays=50)
(log_level=0)
(tracing=no)
(trace_directory=e:\orant\network\trace)
(relay_statistics=no)
(show_tns_info=no)
(use_async_call=yes)
(authentication_level=0)
)

CMAN_RULES=(RULE_LIST=(RULE=(SRC = HOSPNT)(DST = HOSPNT)(SRV = EDP)(ACT = accept)
(SRC = 192.9.200.2)(DST = HOSPNT)(SRV = EDP)(ACT = accept)))


Configuration of Tnsnames.ora( on DEBA machine)
-----------------------------------------
live =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = TCP)
(Host = 192.9.200.6)
(Port = 1521)
)
)
(CONNECT_DATA = (SID = ORCL)
)
)
test =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = TCP)
(Host = 192.9.200.5)
(Port = 1521)
)
)
(CONNECT_DATA = (SID = ORCL)
)
)
ph =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = TCP)
(Host = 192.9.200.4)
(Port = 1521)
)
)
(CONNECT_DATA = (SID = ph)
)
)
edp =
(DESCRIPTION =
(ADDRESS_LIST = #(ADDRESS=(PROTOCOL=TCP)(HOST=HOSPNT)(PORT=1610))
(ADDRESS = (PROTOCOL = TCP)(Host = hospnt)(Port = 1521))
)
(CONNECT_DATA = (SID = edp))
#(SOURCE_ROUTE=YES)
)
Beq-local.world =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = BEQ)
(PROGRAM = oracle80)
(ARGV0 = oracle80ORCL)
(ARGS = '(DESCRIPTION=(LOCAL=YES)(ADDRESS=(PROTOCOL=beq)))')
)
)
(CONNECT_DATA = (SID = ORCL)
)
)
Tcp-loopback.world =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = TCP)
(Host = 127.0.0.1)
(Port = 1521)
)
)
(CONNECT_DATA = (SID = ORCL)
)
)
TcpExample.world =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = TCP)
(Host = Production1)
(Port = 1521)
)
)
(CONNECT_DATA = (SID = ORCL)
)
)
SpxExample.world =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = SPX)
(Service = Server_lsnr)
)
)
(CONNECT_DATA = (SID = ORCL)
)
)
NmpExample.world =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(PROTOCOL = NMP)
(Server = FinanceServer1)
(Pipe = ORAPIPE)
)
)
(CONNECT_DATA = (SID = ORCL)
)
)
CMExample.world =
(DESCRIPTION=(address_list=
(ADDRESS=
(PROTOCOL=tcp)(PORT=1610)(HOST=CM_SERVER))
(ADDRESS=
(PROTOCOL=tcp)(PORT=1521)(HOST=LSNR_SERVER)))
(CONNECT_DATA=(SID=ORCL))
(SOURCE_ROUTE=yes)
)
extproc_connection_data.world =
(DESCRIPTION =
(ADDRESS =
(PROTOCOL = IPC)
(KEY = EXTPROC%ORACLE_HOME_ID%)
)
(CONNECT_DATA = (SID = extproc)
)
)

Configuration of Sqlnet.ora( on DEBA)
-------------------------------------
TRACE_LEVEL_CLIENT = OFF
#sqlnet.authentication_services = (NONE)
names.directory_path = (TNSNAMES, HOSTNAME)
#names.default_domain = world
#name.default_zone = world
#automatic_ipc = off
USE_CMAN=TRUE

Now I am using Developer 6 (Forms 6) on DEBA machine to connect to the EDP
database on HOSPNT machine and the service name is also EDP.Now I have started
Listener , service , database and CMAN on HOSPNT.Now I connect to EDP database
( without removing comment) then it is connected . It implies NO CMAN is used.
If I connect to the EDP database removing the comments against EDP service string
, then it is giving the same error . Removing comments means that CMAN is used.

If I try to connect from another machine(192.9.200.3) using Forms 4.5
through CMAN the same error is coming. So there is no compatibility prob.

Network is there . Ping is possible among all the machines on the network.
So there is no network problem.

I have also commented Sqlnet.authentication_service in Sqlnet.ora. But no
result . Where is the problem ?