Once again, Sergio was complaining because matches inside svn folders were showing up in search results. Since I like challenges, I wrote this small Eclipse plugin that excludes .svn and CVS folders from searches.
Here's the relevant file (contains also the source code).
To activate it, first copy it to your plugins folder, restart Eclipse, go to Windows -> Preferences -> General -> Search and select "Better Search Engine" in "Text Search Engine to be used".
Update: Here's the same plugin for Eclipse 3.5 (the other won't work).