function isEmail(email) {
    invalidChars = " ~\'^\`\"*+=\\|][(){}$&!#%/:,;";

    // Check for null
    if (email == "") {
        return true;
    }

    // Check for invalid characters as defined above
    for (i=0; i<invalidChars.length; i++) {
        badChar = invalidChars.charAt(i);
        if (email.indexOf(badChar,0) > -1) {
            return false;
        }
    }
    lengthOfEmail = email.length;
    if ((email.charAt(lengthOfEmail - 1) == ".") || (email.charAt(lengthOfEmail - 2) == ".")) {
        return false;
    }
    Pos = email.indexOf("@",1);
    if (email.charAt(Pos + 1) == ".") {
        return false;
    }
    while ((Pos < lengthOfEmail) && ( Pos != -1)) {
        Pos = email.indexOf(".",Pos);
        if (email.charAt(Pos + 1) == ".") {
            return false;
        }
        if (Pos != -1) {
            Pos++;
        }
    }

    // There must be at least one @ symbol
    atPos = email.indexOf("@",1);
    if (atPos == -1) {
        return false;
    }

    // But only ONE @ symbol
    if (email.indexOf("@",atPos+1) != -1) {
        return false;
    }

    // Also check for at least one period after the @ symbol
    periodPos = email.indexOf(".",atPos);
    if (periodPos == -1) {
        return false;
    }
    if (periodPos+3 > email.length) {
        return false;
    }
    return true;
}

/*
==================================================================
LTrim(string) : Returns a copy of a string without leading spaces.
==================================================================
*/
function LTrim(str)
/*
   PURPOSE: Remove leading blanks from our string.
   IN: str - the string we want to LTrim
*/
{
   var whitespace = new String(" \t\n\r");

   var s = new String(str);

   if (whitespace.indexOf(s.charAt(0)) != -1) {
      // We have a string with leading blank(s)...

      var j=0, i = s.length;

      // Iterate from the far left of string until we
      // don't have any more whitespace...
      while (j < i && whitespace.indexOf(s.charAt(j)) != -1)
         j++;

      // Get the substring from the first non-whitespace
      // character to the end of the string...
      s = s.substring(j, i);
   }
   return s;
}

/*
==================================================================
RTrim(string) : Returns a copy of a string without trailing spaces.
==================================================================
*/
function RTrim(str)
/*
   PURPOSE: Remove trailing blanks from our string.
   IN: str - the string we want to RTrim

*/
{
   // We don't want to trip JUST spaces, but also tabs,
   // line feeds, etc.  Add anything else you want to
   // "trim" here in Whitespace
   var whitespace = new String(" \t\n\r");

   var s = new String(str);

   if (whitespace.indexOf(s.charAt(s.length-1)) != -1) {
      // We have a string with trailing blank(s)...

      var i = s.length - 1;       // Get length of string

      // Iterate from the far right of string until we
      // don't have any more whitespace...
      while (i >= 0 && whitespace.indexOf(s.charAt(i)) != -1)
         i--;


      // Get the substring from the front of the string to
      // where the last non-whitespace character is...
      s = s.substring(0, i+1);
   }

   return s;
}

/*
=============================================================
Trim(string) : Returns a copy of a string without leading or trailing spaces
=============================================================
*/
function Trim(str)
/*
   PURPOSE: Remove trailing and leading blanks from our string.
   IN: str - the string we want to Trim

   RETVAL: A Trimmed string!
*/
{
   return RTrim(LTrim(str));
}