loadPatterns = function (lang) {
		var url, xhr, head, script;
		if (supportedLang[lang] && !Hyphenator.languages[lang]) {
	        url = basePath + 'patterns/' + supportedLang[lang];
		} else {
			return;
		}
		if (isLocal && !isBookmarklet) {
			//check if 'url' is available:
			xhr = null;
			if (typeof XMLHttpRequest !== 'undefined') {
				xhr = new XMLHttpRequest();
			}
			if (!xhr) {
				try {
					xhr  = new ActiveXObject("Msxml2.XMLHTTP");
				} catch (e) {
					xhr  = null;
				}
			}
			if (xhr) {
				xhr.open('HEAD', url, false);
				xhr.setRequestHeader('Cache-Control', 'no-cache');
				xhr.send(null);
				if (xhr.status === 404) {
					onError(new Error('Could not load\n' + url));
					delete docLanguages[lang];
					return;
				}
			}
		}
		if (createElem) {
			head = window.document.getElementsByTagName('head').item(0);
			script = createElem('script', window);
			script.src = url;
			script.type = 'text/javascript';
			head.appendChild(script);
		}
	}
@name Hyphenator-loadPatterns
@description
Adds a &lt;script&gt;-Tag to the DOM to load an externeal .js-file containing patterns and settings for the given language.
If the given language is not in the {@link Hyphenator-supportedLang}-Object it returns.
One may ask why we are not using AJAX to load the patterns. The XMLHttpRequest-Object 
has a same-origin-policy. This makes the isBookmarklet-functionality impossible.
@param {string} lang The language to load the patterns for
@private
@see Hyphenator-basePath