Ticket #17168: 17168.diff

wp-admin/network.php

@@ -87 +87 @@
         if ( $existing_domain = network_domain_check() )
                 return $existing_domain;
         $domain = preg_replace( '|https?://|', '', get_option( 'siteurl' ) );
+        $domain = strtolower( $domain );
         if ( $slash = strpos( $domain, '/' ) )
                 $domain = substr( $domain, 0, $slash );
         return $domain;