How can I connect to a SVN repository via a proxy server?

My company's Subversion (SVN) server requires the use of a proxy server to access it. It's the same proxy server as we use for Internet access.

I've configured the proxy in MATLAB's Web Preferences, and it works for Web access e.g. the Add-on Explorer.

However when I follow the instructions to set up SVN access in MATLAB, click 'Change' next to 'Repository path', enter the repository URL and click 'Validate', I get an 'Invalid path' error (Could not get repository URL: svn: E175002: unknown host). If I try to continue and click 'Retrieve' I get a 'Could not checkout repository at location: ...' error.

Does MATLAB's built-in SVN integration use the proxy settings in Web Preferences to connect to the SVN server, or do I have to set this up some other way - e.g. do I have to install SVN myself and use command-line SVN integration instead?