Sharepoint SSO bulk creation of user accounts

Hopefully someone can help...

I need to provide client with a solution to allow bulk creation of user accounts into SharePoint SSO. The client wants to provide an excel spreadsheet with accounts, usernames and passwords and have that created in the SSO database.

I've been told its possible but I can't see how and goo开发者_高级运维gle is failing me. I've been told its "some custom development and the SharePoint object model". As far as I can see all of the credentials stuff in the Microsoft.SharePoint.Portal.SingleSignon namespace is very much read only.

I have a solution which is to get them to save the spreadsheet as a CSV file and to use jmeter to squirt the data in through the front end. I don't think that's really an acceptable solution though.

Anyone got any clues? Or can anyone say definitively this can't be done?

Thanks in advance...

You can store the user credentials in Active directory or SQL database based on the authentication method. You can write code for copy these credential in the AD/database.