Ok I know what's going on. When you run your comma...

# kobalt

[cedric]

Ok I know what's going on. When you run your command SLF4J issues

0 = "SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder"."
1 = "SLF4J: Defaulting to no-operation (NOP) logger implementation"
2 = "SLF4J: See <http://www.slf4j.org/codes.html#StaticLoggerBinder> for further details."

on stderr, which Kobalt interprets as "something went wrong".