Sys.Data.DataContext and DateTime

 I currently have my business logic and data layer built and am returning custom objects.  I don't know if the AdoDataContext object works correctly, but my application supports multiple data sources and the AdoDataContext doesn't apply.  Why doesn't the DateTime object get marshaled properly.  To ensure data concurrency I have three important types returned from every object:
RecordID int
CreateDate DateTime
LastUpdated DateTime
For some reason the DateTime object that is returned back from my ASPX page is always dsplayed and brought back to the client properly.  When I call saveChanges on my DataContext the datetime object that is marshaled back is always incorrect which is preventing my database records to be updated correctly.  Has anyone experienced this?
 
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