How can I make Claws Mail send my compface image in the mails?
In the Configuration menu, Preferences for current account, Send tab, check Add user-defined header and press Edit button. A dialog appears, add a header named “X-Face” and fill the value field with your face data. Alternatively, you can select a .xbm file in this dialog. Note that if you paste the data from a terminal into the field some spurious newlines can be added, and these can mangle your face, be careful.