Losing MainDocumentType on Open()

Hey guys, I have a mail merge document that is set to Directory for the Main
Document Type. If I close it and manually reopen it, it stays as a
"Directory" document, but if I open it through automation (i.e.
oWord.Documents.Open("C:\SomeDirectory\SomeDirecto ryDocument.doc")) the
oWord.ActiveDocument.MailMerge.MainDocumentType = -1 as soon as you do the
Open() command and then it gets set to 0 once you call the OpenDataSource().

How can I open the document through automation and keep the document type
that the user originally saved it with?


Thanks for your help,

Jerry