Subsonic 3 injects the column TestMode on a join

Question

return (from sge in Context.SecurityGroupEmployees
               join sg in Context.SecurityGroups on sge.SecurityGroupId equals sg.SecurityGroupId
               join lu in Context.Lookups on sg.SecurityGroupTypeId equals lu.LookupId
               where lu.Value == value
               select sge.Employee).ToList();

the above code wants to add 'TestMode' column on a join with an AND operator on the left. This Field only exists in the active object as a Field not a Property. I have been digging through the source trying to stop this from happening, however I am spinning my wheels in trying to find the root of the problem. because Linq to Subsonic is adding the TestMode it generates invalid SQL that errors out every time. in particular the 'TestMode' is added to the second JOIN. thank you for feedback.