The following layout works as expected when in a FileAppender or RollingFileAppender

<layout class="ch.qos.logback.classic.PatternLayout">
<pattern>%date [%thread] %-5level %logger %n%n Class : %class %n Line : %line %n%n%message%n</pattern>
</layout>

but when in an SMTPAppender, the class and line conversion words only produce a '?' instead of their correct values.

This was working in 0.9.24 (my last used version).

Chris