From: Koosha Khajehmoogahi Date: Mon, 23 Mar 2015 01:11:04 GMT Subject: git-send-email.perl should check the version of Perl modules it uses Message-ID: <550F6828.2090602@posteo.de> On Debian Wheezy with its outdated packages, the version of Net::SMTP::SSL is 1.01. If you try to use send-email, the script will crash with the following error: STARTTLS failed! SSL connect attempt failed with unknown error error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed at /usr/libexec/git-core/git-send-email line 1294 Apparently, that is because the script is calling a subroutine (start_SSL()) that is missing in older versions. I guess the script should check the minimum required version before proceeding with the execution.