The attributes needed to specify to connect to eDirectory are “connectionUsername” and “connectionPassword” as the sample shown below: 
<add name="membership"
     type="Microsoft.Office.Server.Security.LdapMembershipProvider, Microsoft.Office.Server, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c"
     server="LDAP server"
     port="389"
     useSSL="false"
     userDNAttribute="entryDN"
     userNameAttribute="name"
     userContainer="OU=,O="
     userObjectClass="person"
     userFilter="(&amp;(ObjectClass=person))"
     scope="Subtree"
     otherRequiredUserAttributes="cn"
     connectionUsername="user DN"
     connectionPassword="password" />

you also need to make sure the attribute mapping is correct. Lots of sample on net has userDNAttribute = “distinguishedName” which is from Windows AD or LDAP service.