Mail.app and *.tex attachments

I have a very annoying problem with mail.app. When I receive emails with LaTex file attachments, mail.app does not download the attachment but it just display the code of the file so I have to copy all the code to a new latex file. This process is very inconvenient. Does anybody know how to fix this problem ? Please help me, I love apple mail and don't want to switch to Thunderbird just because of this problem
Thank in advance & sorry for my bad english

 

My problem is that mail.app doesn't even display the save button , it automatically displays the LaTex code and treats my mail as there's no attachment