ssh error message

[Simper, Brian D]

Whenever I use secure shell on my Linux servers these error messages appear in /var/log/messages:

Aug 18 09:43:40 test-desk sshd(pam_unix)[28553]: authentication failure; logname= uid=0 euid=0 tty=NODEVssh ruser= rhost=test-mobl2.amr.corp.com  user=test
Aug 18 09:43:49 test-desk sshd(pam_unix)[28555]: session opened for user test by (uid=500)

Aug 28 09:44:20 test-desk sshd(pam_unix)[28590]: authentication failure; logname= uid=0 euid=0 tty=NODEVssh ruser= rhost=uelinux.corp.com  user=test
Aug 28 09:44:33 test-desk sshd(pam_unix)[28592]: session opened for user test by (uid=500)

The SSH session works but I get this authentication failure message appearing.  I am guessing that this is not a problem, but does anyone know what it means and what causes it?

Thanks,

Brian