I'm trying to connect to a server but if i use any other user than root the connection closes itself after a successful login:

XXXXXXX:~ user$ ssh -v [email protected]
OpenSSH_5.2p1, OpenSSL 0.9.8l 5 Nov 2009
debug1: Reading configuration data /etc/ssh_config
debug1: Connecting to XXXXXXX.XXXXXX.XXX [xxx.xxx.xxx.xxx] port 22.
debug1: Connection established.
debug1: identity file /Users/user/.ssh/identity type -1
debug1: identity file /Users/user/.ssh/id_rsa type -1
debug1: identity file /Users/user/.ssh/id_dsa type 2
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH_4*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.2
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Host 'XXXXXXX.XXXXXX.XXX' is known and matches the RSA host key.
debug1: Found key in /Users/user/.ssh/known_hosts:12
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug1: Next authentication method: publickey
debug1: Offering public key: /Users/user/.ssh/woo_openssh
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug1: Offering public key: /Users/user/.ssh/sidlee.dsa
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug1: Trying private key: /Users/user/.ssh/identity
debug1: Trying private key: /Users/user/.ssh/id_rsa
debug1: Offering public key: /Users/user/.ssh/id_dsa
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug1: Next authentication method: password
[email protected]'s password: 
debug1: Authentication succeeded (password).
debug1: channel 0: new [client-session]
debug1: Entering interactive session.
Last login: Mon Mar 29 01:41:51 2010 from 193.67.179.2
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug1: channel 0: free: client-session, nchannels 1
Connection to XXXXXXX.XXXXXX.XXX closed.
Transferred: sent 2976, received 2136 bytes, in 0.5 seconds
Bytes per second: sent 5892.2, received 4229.1
debug1: Exit status 1

If i log in as root the exact same way it works as expected.

I've added the users i want to log in with to a group (sshusers) and added that group to /etc/sshd_config:

AllowGroups sshusers

I'm not sure what to try next as i don't get a clear error anywhere. I would like to enable specific accounts to log in so that i can disable root.

This is a GridServer/Media Temple (CentOS).