Account on Android problem

Hi all,
New build 730 running on SLES 11 SP 1 fully patched. Two Android devices - Samsung GT-P7500 with Android 3.2 and second HTC Desire A8181 with Android 2.2.2. Both have problem creating account for user (tried few usernames).
Samsung says wrong user/password, HTC that Exchange policy not allow ...
I created user on iPhone and on HTC Desire Z (Droid 2.3.3) without problems.
Checked combination in username with "\" and without. Also changed authentication to GW (LDAP authentication is used).
We have no SSL turned on.
Any solutions ?
Regards,
Maciej