[Evolution] content type of attachments

[Scott Dixon <scott metaphorics com>]

Hi,
Someone has recently pointed out to me that a text file I sent as an
attachment (with a file name extension of .dat) was labeled as content
type video/mpeg.  Where is that controlled?  I don't see .dat as being
set as video/mpeg in the mimetypes capplet for example.  Is there some
place to control how the content type is set?
Scott