Error while installing ESM agent

hi,

i am running symantec enterprise manager v 10.0.

when i am installing esm agent on client it is giving below error: pls help if anybody has answers to it:

[13820] register: Args List: -r -v -m 10.X.X.X -p 5600 -t -N XYZ -u -E
[13820] register: Agent registration starting ......
[13820] register: Registering to Manager: 10.X.X.X
[13820] register: 2013/06/21 19:45:19:648: Mode NA2 DH1024 RV8
[13820] register: User is authorized to register agents with manager
[13820] register: Password is not expired
      registering agent information
[13820] register: Registering agent information
    loading agent information
    adding 10.X.X.X to ESM manager access control file
    exchanging authentication keys
    Verifying Manager to Agent communication
Connection verification from the Manager to the Agent XYZ failed
Failed to continue with the registration process
[13820] register:  Error: ESM_REG_23888, Error occured while opening connection to XYZ [13820] register:  Error: ESM_REG_23673, Error occured while contacting agent XYZ 
<AxStringCode Code=23872>Error occured while opening connection on port %1</AxStringCode> 1 5601 
<AxStringCode Code=22363>hostname %1 not found: err=%2</AxStringCode> 2 XYZ 11004