Keeping Custom Properties When Forwarding or Replying to a Message
 

We have emails saved on the file system, that is kept track of by
another program. These emails have custom properties attached to
them. There is no custom form, just custom properties. These fields
were originally added using objPost.UserProperties.Add. We need it
so that when someone opens up one of these emails through the file
system, and then replies or fowards the message, these custom
properties are kept in the reply. This is so the external program can
track these emails. Is there a way this can be done? We could have
these emails opened up using an Outlook command line that includes a
path to a macro. We are using Outlook 2000 and Outlook 2002.