Compared to CVS, SVN has some novel features, one of which is (versioned) properties. These are used internally in SVN (like svn:keywords, svn:ignore), but they also provide a convenient hook into various SVN tool sets.
One such tool, the popular TortoiseSVN shell extension, was the first to define properties for controlling integration to issue tracker systems (like Bugzilla, etc.), enabling a special field for entering an issue number/identifier with each commit, and supporting a direct link from a log (History) message back to the issue tracker.
These properties and the expected behavior of the tool are described at: <http://guest:guest@tortoisesvn.tigris.org/svn/tortoisesvn/trunk/doc/issuetrackers.txt>
The SVN plug-in supports the following Issue tracking properties:
Support for issue trackers is covered in the Commit and Branch/Tag dialogs, and the SVN Resource History View.
In the history view, a hyperlink is displayed to launch the issue tracking system in a browser (if configured). Many popular issue tracker systems can be integrated with using this approach.