Unfortunately we do not have such an example ready. We do have a code library
that is quite outdated outdated and is using the old Scope basec approach to OpenAccess. However it should give you an idea as to how to approach this problem and implement your own custom membership provider based on OpenAccess.
And if you decide to do so, it would be great if you could share it with the community trough a code library.
All the best,
the Telerik team
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