The file syslog-ng.conf.gentoo.hardened in the doc directory of app-admin/syslog-ng-1.6.11 (possibly in other versions too) has got a small mistake in it - the facility selected by the filter f_uucp is cron, not uucp. Attached you will find a patch correcting this issue so that the example can be used correctly as it is.
Created attachment 91605 [details, diff] syslog-ng.conf.gentoo.hardened-nouucpbug.patch
*** Bug 140169 has been marked as a duplicate of this bug. ***
This bug is fixed. Thanks for reporting and for the patch.