This is easiest to describe by giving you an example.
1. Visit http://www.crca.org.au/Downloads (anonymous user is fine).
2. Type in a Download tag to find (eg "2009 Synod").
3. Click "Apply"
Result is that the correct results are shown where expected in the Downloads section, but in addition, the Ajax congregation locations form in the page footer gets replaced with another copy of the search form and results. (I'd expect just the top one to change, and the congregation links to stay there). A similar thing happens in reverse.
Interestingly, the issue is not seen if you've got filtering already in place. If you do:
1. Visit http://www.crca.org.au/Downloads
2. Select a state in the congregations and click Apply.
3. Type in a tag in the Downloads and click apply.
... then everything works as expected.
FAILED: [[SimpleTest]]: [MySQL] Unable to apply patch views_655002_46.patch. Unable to apply patch. See the log in the details link for more information.
PASSED: [[SimpleTest]]: [MySQL] 0 pass(es).
FAILED: [[SimpleTest]]: [MySQL] Unable to apply patch 981870-safe-dom-id.patch. Unable to apply patch. See the log in the details link for more information.