SVN import requires authentication

I'm trying to import a Subversion repository into Launchpad using this access info: http://joomlacode.org/gf/project/rsgallery2/scmsvn/?action=AccessInfo. The repository requires that I enter the username "anonymous" and no password to checkout a copy. Launchpad marked my attempted import invalid for this reason: "Rejected: repository demands authentication" So I tried entering this URL into the import system: http://anonymous:@joomlacode.org/svn/rsgallery2. This works as a svn checkout url on my local machine, but Launchpad tells me "A username may not be specified in the URI." Is there any way for me to import this repository? The Launchpad project into which I'm trying to import the repository is https://launchpad.net/rsgallery.

Thank you for your help!