Thanks, Michael. I did look at find and read both of these links before
posting, but neither sheds any more light on why this particular error is
showing up.
Since you did not provide any details about the entry in question there's no
possibility to give a more detailed answer.
You might wanna browse the entry in question with a LDAP client with decent
schema support. I guess the object class(es) do not allow attribute
userPassword.