[logback-user] class & line conversion words not working

I have just upgraded to logback 1.0 (from 0.9.x), and now the conversion words for %class and %line just produce a question mark. My pattern layout is <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> Prior to the update this was working and now it's not. Everything else in the layout displays as specified, except %class and %line. I do have the java compiler generating debug information too. Any suggestions? Chris