If you're setting up your OpenLDAP Server with Samba support according to the following tutorials:

You will probably stick at the following line.

ldapsearch -xLLL -D cn=admin,cn=config -x -b cn=config -W olcDatabase={1}hdb
Enter LDAP Password:
ldap_bind: Invalid credentials (49)

This issue is based on the problem, that somehow the olcRootPW isn't correctly set, following the instructions of the following solved this issue for me:
http://ubuntuforums.org/showpost.php?p=10227690&postcount=3