Your clients can use their own WebID to use the web panel, and you can grant privileges to their WebId.
- Create the announcement list
- If the client doesn't have their own webid, create user and then a webid for the user.
- Grant mailing list privileges to the webid.
- Client logins into web panel
From the Wiki - KB / Account Control Panel / Billing :: Account Privileges
"You can choose to give a web ID access to any specific mailing list of yours, or access to all mailing lists you have. Mailing list access allows a web ID to modify the properties/subscribers to a mailing list as well as to post to the mailing list from the web panel. They can also delete the mailing list but won't be able to add one unless they have DOMAIN access to the domain they want to add it to. In a way, mailing list access is a sub-set of DOMAIN access."
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