SMTPAppender_GreenTest fails on my machine. It seems GreenMail is not yet ready to receive mails when the mails are triggered by the smtpAppender:

Failed tests: html(ch.qos.logback.classic.net.SMTPAppender_GreenTest): expected:<1> but was:<0>
syncronousSmoke(ch.qos.logback.classic.net.SMTPAppender_GreenTest): expected:<1> but was:<0>
LBCLASSIC_104(ch.qos.logback.classic.net.SMTPAppender_GreenTest): expected:<1> but was:<0>
bufferShouldBeResetBetweenMessages(ch.qos.logback.classic.net.SMTPAppender_GreenTest): expected:<2> but was:<0>

Adding some delay after the greenmail server intialization -in SMTPAppender_GreenTest) fixes the issue:

greenMailServer.start();
Thread.currentThread().sleep(2000);

Debian