Rated 5 out of 5 stars

Yeah this is kind of cool and does what it states very well!

Only thing left is to do it the other way round*: Usually I have "digitally sign by default" activated and want it to deactivate this for certain contacts. So a good addition would be to add the switch no-sign and possibly no-encryt.

Keep up the good work!

*[EDIT] nosign and noencrypt is working like a charm in the new version. Thanks! :)

This review is for a previous version of the add-on (0.1.2). 

Nice idea, no-sign and no-encryt, I'll do that in the next version.

PS: sent you an e-mail.