Getting Error Code to print while using LogBack.

[Vic Hood]

Hi folks ,
I'm trying to implement the SLF4J +LogBack logging solution to implement logging in my application .
I've modified the Pattern Expression in the logback.xml as below.
<Pattern>%d{dd MMM yyyy HH:mm:ss.SSS} %logger{36} %M-%msg%n</Pattern>

And its working fine . However I'd like to print the 'error code ' as well in my log say 404 or 500 as well . Any ideas on how I should be modifying my pattern expression for this?
Thanks.