Language sitemaps not submitted correctly in multilanguage sites

If you are having multilingual site, only system installation specific language sitemap is submitted to search engines - multiple number of times.

Problems lies in xmlsitemap_engines_submit_sitemaps function where original $url variable gets override inside foreach loop (and xmlsitemap_engines_prepare_url function is unable to replace [sitemap] token with proper sitemap url]

Original:

function xmlsitemap_engines_submit_sitemaps($url, $sitemaps = array()) {
  foreach ($sitemaps as $sitemap) {
    $url = xmlsitemap_engines_prepare_url($url, $sitemap);
    $request = drupal_http_request($url);
    watchdog('xmlsitemap', 'Submitted the sitemap to %url and received response @code.', array('%url' => $url, '@code' => $request->code));
  }
}

Corrected:

function xmlsitemap_engines_submit_sitemaps($url, $sitemaps = array()) {
  foreach ($sitemaps as $sitemap) {
    $url_submit = xmlsitemap_engines_prepare_url($url, $sitemap);
    $request = drupal_http_request($url_submit);
    watchdog('xmlsitemap', 'Submitted the sitemap to %url and received response @code.', array('%url' => $url_submit, '@code' => $request->code));
  }
}