Prerequisites: Enable the blog system (enableblogs) and RSS feeds (enablerssfeeds) on your system; both found in "Site administration -> Advanced features" Set debugging to "Developer" level. Also, make sure that back-end PHP error messages are directed to a log file (e.g., Apache's error.log). Add a course (C) and there, add the "Blog menu" block. Enrol a user U into the course C. Logged in as U, go to C, click "Add an entry about this course" and complete the form. Main steps: Purge all caches (Site administration -> Developer -> Purge all caches) Log in as U, go to C and click on "Blog RSS feed" VERIFY: Feed is being displayed (e.g. in Firefox it's displayed in the browser window) VERIFY: There is no new warning message in the error log. It may be best to first tun the "Main steps" above without the patch applied, to be sure that you are seeing the error messages; then run them with the patch applied and verify that the messages are now absent.