Yes this seems to be a case that is not handled well. We will fix things there. You can remove the ADO type and converter from the rlinq file. OpenAccess calculates a default SQL type from the CLR type and a default converter to convert between these types.
So at the minimum you need only the CLR type but if the sql type is there you can keep it. You should remove the converter and ADO type.
Do get back in case you need further assistance.
the Telerik team
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