Outlook Macro Loses First Message Category

Outlook 2007 categories are behaving very strangely. In particular, the first category of a set message is getting removed. Why is this happening?

To reproduce do the following:

Create a new email message (put yourself as the recipient)
Run the attached macro on it.
Save the message.
Look in Drafts to see that the message has all three categories.
Send the message.
Look in both sent items and inbox to verify that the c\Veracode category has been removed.

Sub Test()
    Dim msg As Outlook.MailItem
    Debug.Print "In Test"
    Set msg = Application.ActiveInspector.CurrentItem
    msg.Categories = "c\Veracode,c\SiCortex,c\8Ring"
    Set msg = Nothing
End Sub

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