US Telephone number validation fails

Hello,

I have the following code that, among other things, should validate US telephone numbers with format: "(800) 800-8000" with hyphen, parenthesis and spaces optional. The regexp is: /^\(?(\d{3})\)?[- ]?(\d{3})[- ]?(\d{4})$/

My main problem is that it validates also numbers like 800 or 800000000000000 etc.
The code works perfectly on test pages but not on my website.
Something similar happens also for the zipcode.

Can someone please tell me what could be wrong?
Thanks!

(function($){
$.fn.ax_validate = function(f){
stopAnim(); // just too much otherwise
//console.log(typeof f + ', id = ' + f.id);
var n, el, err = [], msg = [],
fmats = {
'email': /^[\w\.\-]+\x40[\w\.\-]+\.\w{2,4}$/,
'phone': /^\(?(\d{3})\)?[- ]?(\d{3})[- ]?(\d{4})$/,
'zip': /^\d{5}(-\d{4})?$|[ABCEGHJKLMNPRSTVXY]\d[A-Z] \d[A-Z]\d/
};

$('input[type=text],textarea').each(function(i){
$(this).val( $.trim($(this).val()) );
});

$('label.req').each(function(i){
n = $(this).attr('for');
el = $('input[name=' + n + ']');

if (typeof fmats[n] != 'undefined' && !el.val().match(fmats[n])) {
err.push(n);
msg.push($(this).text() + ((el.val() == '') ? '' : ' (invalid format)'));
$(this).animate({color: '#A60'}, 1000);

} else if (el.val() == '') {
err.push(n);
msg.push($(this).text());
$(this).animate({color: '#A00'}, 1000);

} else {
$(this).css('color', '#0f4068');
}
});
if (err.length == 0) {
//alert('All ok!');
//f.submit();
return true;
}
alert('<b>Please fix the following required fields:</b><br /><br />' + msg.join('<br />'));
//$('input[name=' + err[0] + ']').focus();
return false;
};
})(jQuery);

EDIT
=======
removed my attempt since after trying original reg ex I couldn't find(see) anything wrong with it.

sorry
LT

Nothing wrong with the regexes.

if (typeof fmats[n] != 'undefined' && !el.val().match(fmats[n])) {


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