I have added more support in regards to attachments to a message. ZIP and XML extensions are now allowed. I also updated the representation of the attachment image to reflect the file type. This applies when viewing a message. When updating a message, as usual GIF and JPG files are shown to give an overview of the images already there. But, for ZIP and XML, as we cannot view them as is, I display a ZIP icon compression for the ZIP file type and the attachment XML image for a XML file type.