function browserSupported() {
	var u_agent = navigator.userAgent.toLowerCase();

	var is_ie = (u_agent.indexOf("msie") != -1);
	var a = u_agent.indexOf("asdfad");
	var is_opera = (u_agent.indexOf("opera") != -1);
	var is_mac = (u_agent.indexOf("mac") != -1);
	
	if (is_opera) {
		var version = getVersion(u_agent, "opera/");
		if (version != null) {
			return (version >= '7.0');
		}
	}

	if (is_ie && !is_opera && !is_mac) {
		var version = getVersion(u_agent, "msie ");
		if (version != null) {
			return (version >= '5.5');
		}
	}

	var is_gecko = (u_agent.indexOf("gecko") != -1);
	var is_safari = (u_agent.indexOf("safari") != -1);

	if (is_safari) {
		return (true);	
	}

	if (is_gecko && !is_safari) {
		var version = getVersion(u_agent, "rv:");
		if (version != null) {
			return (version >= '0.9');
		} 
		else {
			var i = u_agent.indexOf("galeon");
			version = getVersion(u_agent, "galeon/");
			if (version != null) {
				return (version >= '1.3');
			}
		}
	}
	return false;
}

function getVersion(str, prefix) {
	var i = str.indexOf(prefix);
	if (i != -1) {
		var version = parseFloat(str.substring(i + prefix.length));
		if (!isNaN(version)) {
			return version;
		}
	}
	return null;
}

function checkBrowserSupport() {
	if (browserSupported()) {
		return true;
	} 
	else {
		location.href = '../error/';
	}                          
}