Application Manager 11 cannot discover some AIX servers

Hi all,

I've just installed Application Manager 11 to monitor several AIX servers. I've encountered the error "Discovery failed for the configured resource.Refer our troubleshooting section for more details" when I 've tried adding some of my servers to monitor.

Strange that several AIX servers work fine with AppManager 11, some don't. They are all AIX 5.3, monitored via telnet.

Consider the AIX server that cannot be added to AppMan11 is 10.228.13.4. I've found these log in the stderr.txt when adding the server:

[22 Jan 2013 06:01:11:772] ME-AM: Calling discoverHost {HOST_CONFIG={10.228.13.4:23={HOST_IP=10.228.13.4, SERVER_TYPE=SYSTEM, SUBNET_MASK=255.
255.255.0, PORT=23, popPort=110, sslenabled=false}}, DISC_DATA_PROP={REDISCOVER_INTERVAL=24, HOUR=-1}}DC Props {addasip=false, addtoapplicatio
n=false, username=itbl, sslenabled=false, WTEnabled=false, os=AIX, prompt=$ , givenhost=10.228.13.4, eventlog_status=false, ndhost=10.228.13.4
, haid=-, DISPLAYNAME=10.228.13.4_OCS_1_1, TELNETPORT=23, hostdiscovery=newmonitor, MODE=TELNET, pollinterval=300}
[22 Jan 2013 06:01:12:233] ME-AM: Host Resource : Authentication check passed as Monitoring Initiated Successfully. for host of typeAIX in 10.
228.13.4 : 23
[22 Jan 2013 06:01:12:233] ME-AM: CHECKALREADYEXISTSSSSSSSS null    Host IP that trying to add: 10.228.13.4
[22 Jan 2013 06:01:12:712] ME-AM: HOSTDISCOVERYADDNODE RESULT:   Successfully Added to Database     Host IP that trying to add: 10.228.13.4
[22 Jan 2013 06:01:14:223] ME-AM: CHECKALREADYEXISTSSSSSSSS 2222 null    Host IP that trying to add: 10.228.13.4
[22 Jan 2013 06:01:14:250] ME-AM: Conf monitor check for SYSTEM:9999, Conf monitors list::[RabbitMQ, Hyper-V-Server, AzureRoleInstance, Memcac
hed, MAIL-server, VirtualMachine, FTPMonitor, OracleEBS, Amazon, WebsphereMQ, EC2Instance, SSLCertificateMonitor, VMWare ESX/ESXi, RDSInstance
, QueryMonitor, SilverStream, MongoDB, GlassFish, Cassandra, WindowsAzure, PostgreSQL, VMware vFabric tc Server]

Well, there's not even an error log, and I don't know where to start to debug this.

Please show me some clues.

Thanks.