Unable to install locally available extension if download unavailable

I have installed my Flo2Cash extensions, and Eileen's PayStation and OMNGateway extensions via Git checkout to /path/to/site/civicrm/extensions

I can enable both Flo2Cash and the OMNGateway, but the PayStation extension cannot be installed because the download URL is not responding.

(Note that CiviCRM makes no distinction between installing and enabling the extension; the same term is used.)

The error is "warning: file_get_contents(https://svn.fuzion.co.nz/repos/fuzion-code/trunk/civicrm/extensions/nz.co.fuzion.paystation.zip): failed to open stream: Connection refused in /path/to/platforms/civicrm-4.1.2-d6.26/sites/all/modules/civicrm/CRM/Core/Extensions/Extension.php on line 240."