$ldapsearch -x -b 'dc=eos,dc=ntu,dc=edu,dc=sg' 'objectclass=*' 
$getent passwd csyong

Even I can use #su - csyong with success.

But still have problem while logging by GDM

Feb 22 08:16:35 localhost gdm-password][1434]: pam_unix(gdm-password:auth): authentication failure; logname= uid=0 euid=0 tty=:0 ruser= rhost=  user=csyong
Feb 22 08:16:52 localhost gdm-password][1689]: pam_unix(gdm-password:auth): authentication failure; logname= uid=0 euid=0 tty=:0 ruser= rhost=  user=csyong

[1]: http://www.server-world.info/en/note?os=Fedora_17&p=ldap&f=2