Since years i think that the Internet Lockout Feature of IBM Domino is not enough. The function is documented here: IBM Domino Administrator Help
Cite of this document:
There are some usage restrictions for Internet password lockout: You can only use Internet password lockout with Web access. Other Internet protocols and services, such as LDAP, POP, IMAP, DIIOP, IBM® Lotus® Quickr®, and IBM Sametime® are not currently supported. However, Internet password lockout can be used for Web access if the password that is used for authentication is stored on an LDAP server
So documentation tells us, that only HTTP can be secured through inetlockout.
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