In order to proliferate a standards-conform use of headers the corresponding fields should be renamed to "filename": - in the attachment's properties dialog - in composer's attachments listing Reproducible: Always For named MIME-parts, the use of the "filename" parameter within the Content-Disposition header is strongly preferred to a non-standard "name" parameter within the Content-Type header. The latter is only an optional redundancy in order to be compatible with older systems that don't adhere to the RFCs. (See: http://www.imc.org/ietf-smtp/mail-archive/msg05023.html)
IMHO, of course. Usability arguments might be opposing, but I think that this is just as intuitive and - regarding the properties dialog - is rather advanced usage.