[xwiki-users] LDAP secure login

I would like to have XWiki authenticate logins by accessing a local LDAP server and validate the password using SSHA (comparison of hashed login plus salt). Could anyone give me a definitive answer as to whether this can be done using existing extensions? I've gone round in circles reading old posts and JIRA issues, and I'm more lost than before. If it isn't possible with current extensions, could anyone suggest a good approach to implementing support? I had thought to use the LDAP Administration module, so perhaps there's a way to add something small over the top? Any useful responses would be much appreciated. B