Resolution:
1. Add a string property under Administrator&gtBusinessConnect&gtSystem Settings>
Installed Protocols-&gtEDI called "edi.outbound.edifact.customContentType". The default value is "application/edifact".  For the purposes of this article, we will set the Content-Type to be "application/edine".

2. Modifying the $BC_HOME/resource/MimeTypes.ini file to add the Content-Type entry as follows:

add this line:

application/edine;;            x-java-content-handler=com.tibco.ax.fw.mime.EDIFACTDataHandler

3.  Register the MimeTypes.ini file by opening Administrator&gtBusinessConnect -> System Settings -> Installed Protocols -> BusinessConnect Server.  Add the custom property "bc.mailcapFile" and set the property type to  "String".  Specify the full path of your custom mimeTypes.ini filename for this property, such as "D:/tibco/bc/5.2/resource/mimeTypes.ini".  After saving, restart the BC server.

I need to change the "Content-Type" value in the MIME header for the outbound EDIFACT documents I am sending out through Email.How do I configure BC to do this?