I confirm that the patch in comment #1 works on Lucid. Setting the $DirOwner and $DirGroup was essential to have rsyslog to creating new directories that are part of the path to the dynamic files ("/var/log/central/%$YEAR%/%$MONTH%/%$DAY%/%HOSTNAME%.log").
I agree that using "$PrivDropToGroup adm" comes with a bigger risk than using "$PrivDropToGroup syslog" but the former provides out of the box compatibility with other tools like logcheck.
I confirm that the patch in comment #1 works on Lucid. Setting the $DirOwner and $DirGroup was essential to have rsyslog to creating new directories that are part of the path to the dynamic files ("/var/ log/central/ %$YEAR% /%$MONTH% /%$DAY% /%HOSTNAME% .log").
I agree that using "$PrivDropToGroup adm" comes with a bigger risk than using "$PrivDropToGroup syslog" but the former provides out of the box compatibility with other tools like logcheck.