function emailCheck (emailStr) {
	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) {
		alert("Email address seems incorrect (check @ and .'s)")
		return false
	}

	var user=matchArray[1]
	var domain=matchArray[2]
	
	// See if "user" is valid 
	if (user.match(userPat)==null) {
	    // user is not valid
	    alert("The username doesn't seem to be valid.")
	    return false
	}
	
	var IPArray=domain.match(ipDomainPat)
	if (IPArray!=null) {
	    // this is an IP address
		  for (var i=1;i<=4;i++) {
		    if (IPArray[i]>255) {
		        alert("Destination IP address is invalid!")
			return false
		    }
	    }
	    return true
	}
	
	// Domain is symbolic name
	var domainArray=domain.match(domainPat)
	if (domainArray==null) {
		alert("The E-mail address appears to be invalid.")
	    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>4) {
	   alert("The EMail address must end in a three or four letter domain, or a two letter country.")
	   return false
	}
	
	// Make sure there's a host name preceding the domain.
	if (len<2) {
	   alert("This EMail address is missing a hostname!")
	   return false
	}
	
	// If we've gotten this far, everything's valid!
	return true;
}


function trimString (str) {
  while (str.charAt(0) == ' ')
    str = str.substring(1);
  while (str.charAt(str.length - 1) == ' ')
    str = str.substring(0, str.length - 1);
  return str;
}