<span style="white-space:pre">	</span>$.browser.mozilla = /firefox/.test(navigator.userAgent.toLowerCase());
	$.browser.webkit = /webkit/.test(navigator.userAgent.toLowerCase());
	$.browser.opera = /opera/.test(navigator.userAgent.toLowerCase());
	$.browser.msie = /msie/.test(navigator.userAgent.toLowerCase());

<span style="white-space:pre">	</span>if ($.browser.msie && 7 > $.browser.version) {}

<span style="white-space:pre">	</span>if ('undefined' == typeof(document.body.style.maxHeight)) {}

<span style="white-space:pre">	</span>if (!$.support.leadingWhitespace) {}

jQuery.extend({
	browser: function() 
	{
	var
	 rwebkit = /(webkit)\/([\w.]+)/,
	 ropera = /(opera)(?:.*version)?[ \/]([\w.]+)/,
	 rmsie = /(msie) ([\w.]+)/,
	 rmozilla = /(mozilla)(?:.*? rv:([\w.]+))?/, 
	 browser = {},
	 ua = window.navigator.userAgent,
	 browserMatch = uaMatch(ua);

	 if (browserMatch.browser) {
	 browser[browserMatch.browser] = true;
	 browser.version = browserMatch.version;
	 }
	 return { browser: browser };
	},
});

function uaMatch(ua) 
{
 ua = ua.toLowerCase();

 var match = rwebkit.exec(ua)
 || ropera.exec(ua)
 || rmsie.exec(ua)
 || ua.indexOf("compatible") < 0 && rmozilla.exec(ua)
 || [];

 return {
 browser : match[1] || "",
 version : match[2] || "0"
 };
}