function checkMail(emailStr,language) {
	if (!language) language = 0; //default deutsch
	var ue = String.fromCharCode(252); //umlaut
	var emailPat=/^(.+)@(.+)$/;
	var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]";
	var validChars="\[^\\s" + specialChars + "\]";
	var quotedUser="(\"[^\"]*\")";
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
	var atom=validChars + '+';
	var word="(" + atom + "|" + quotedUser + ")";
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
	var matchArray=emailStr.match(emailPat);
	if (matchArray==null) {
		if (language == 0) alert("Die E-Mail-Adresse ist nicht korrekt (achten Sie auf @ und Punkte)."); else alert("Email address seems incorrect (check @ and .'s)");
		return false;
	}
	var user=matchArray[1];
	var domain=matchArray[2];
	if (user.match(userPat)==null) {
    	if (language == 0) alert("Der E-Mail-Username ist nicht korrekt."); else alert("The email username doesn't seem to be valid.");
    	return false;
	}
	var IPArray=domain.match(ipDomainPat);
	if (IPArray!=null) {
		for (var i=1;i<=4;i++) {
		    if (IPArray[i]>255) {
		        if (language == 0) alert("Die Ziel-IP der E-Mail-Adresse ist ung" + ue + "ltig!"); else alert("Destination IP of email address is invalid!");
			return false;
		    }
	    }
	    return true;
	}
	var domainArray=domain.match(domainPat);
	if (domainArray==null) {
		if (language == 0) alert("Die E-Mail-Domain scheint ung" + ue + "ltig zu sein."); else alert("The email domain name doesn't seem to be valid.");
	    return false;
	}
	var atomPat=new RegExp(atom,"g");
	var domArr=domain.match(atomPat);
	var len=domArr.length;
	if (domArr[domArr.length-1].length<2 || 
	    domArr[domArr.length-1].length>3) {
	   if (language == 0) alert("Die E-Mail-Domain scheint ung" + ue + "ltig zu sein."); else alert("The email address must end in a three-letter domain, or two letter country.")
	   return false;
	}
	if (len<2) {
	   var errStr = "";
	   if (language == 0) errStr = "Der Hostname der E-Mail-Adresse fehlt!"; else errStr = "This email address is missing a hostname!"; 
	   alert(errStr)
	   return false;
	}
	return true;
}