4.0.1 strange Active Directory login problem

Hello,

I installed openfire 4.0.1 on an ubuntu server.

Then decided to make it work with my AD domain.

I started to configure..

BaseDN=   ou=Accounts,dc=mydomain,dc="net"

and Administrator DN as

cn=admin,cn=Users,dc=mydomain,dc=net

tested successfully, saved and next step.

username field: sAMAccountName

user filter: (objectClass=organizationalPerson)

tested and able to see users..

next step.

group filter

(objectClass=organizationalPerson)

I saw all users,

After finishing setup..

I was able to see all users in users field..

and set my own user as admin to openfire..

Then i was able to login with my account to webgui of openfire..

But.. whenever i try to login to openfire with spark client.. i get unknown username password error..

not only me.. no AD users can able to login.

What can be the problem?