I upgraded from sysklogd-1.4.1-16 to sysklogd-1.4.1-17. Suddenly the only messages appearing in my log are the messages from sysklogd itself, e.g., "last message repeated" and "syslogd 1.4.1; restart". All the other messages are blank lines. The problem went away when I downgraded back to 1.4.1-16.
*** This bug has been marked as a duplicate of 125650 ***
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2005-087.html