Hi there, I am using ubuntu 9.10, and I would like to associate thunderbird to all the files with the extension .eml. The problem is that is seems that ubuntu is attributing the mime type text/plain to these files, based on their content, which meens that if I set thunderbird as the default application for .eml files, all the other text files (.txt for instance) will be opened with thunderbird. Is it possible to add a rule to impose a mime type based on the file extension, regardless of its content?