ldap_read()

i want to rename an ldap entry by using ldap_read:

ldap_rename($ds,
"ou=old_name,ou=newsletters,ou=applications,dc=test,dc=net",
"ou=new_name,ou=newsletters,ou=applications,dc=test,dc=net")

when viewing errors with "echo $ldap_error($ds);" i get a success
when looking in the directory a see:
"ou=old_name,ou=newsletters,ou=applications,dc=test,dc=net" so nothing
changed!!!!

someone can help me on this?

regards,

Jason