[SVN791] plg_rsg2_display does not work after upgrade from SVN781 to 791

This may be a post for the "templates & display" forum, but I see it as related to SVN791...

With SVN 781, plg_rsg2_display & photobox works nicely, but after installing SVN791, I get:

Warning: require_once() [function.require-once]: open_basedir restriction in effect. File(/administrator/components/com_rsgallery2/init.rsgallery2.php) is not within the allowed path(s): (/home/web/webxxxxx:/var/tmp:/usr/local/lib/php:/usr/local/share/pear) in /usr/home/web/webxxxxx/test/plugins/content/plg_rsg2_display.php on line 37

Warning: require_once(/administrator/components/com_rsgallery2/init.rsgallery2.php) [function.require-once]: failed to open stream: Operation not permitted in /usr/home/web/webxxxxx/test/plugins/content/plg_rsg2_display.php on line 37

Fatal error: require_once() [function.require]: Failed opening required '/administrator/components/com_rsgallery2/init.rsgallery2.php' (include_path='.:/usr/local/share/pear') in /usr/home/web/webxxxxx/test/plugins/content/plg_rsg2_display.php on line 37

As I read it, somewhere in SVN791 the relative path to Joomla root is missing...or the call to GetSiteURL returns null...

Regards
JTA