function textboxDown(textbox, defaultText)
{
	if (textbox.value == defaultText)
	{
		textbox.value = '';
		textbox.focus();
	}
}

function textboxUp(textbox, defaultText)
{
	if (textbox.value == defaultText || textbox.value == '' || textbox.value.length == 0 || !textbox.value.match(/[^\s]/))
	{
		textbox.value = defaultText;
		textbox.style.color = '#3399FF';
		textbox.style.backgroundColor = '#C0CEE0';
		textbox.style.fontStyle = 'italic';
	}
	else
	{
		textbox.style.color = '#000000';
		textbox.style.backgroundColor = '#ffffff';
	}
}

function textboxFocus(textbox, defaultText)
{
	if (textbox.value == defaultText)
		textbox.value = '';
	textbox.style.color = '#000000';
	textbox.style.backgroundColor = '#ffffff';
	textbox.style.fontStyle = 'normal';
}

function checkForm(defaultName, defaultEmail, defaultMessage) {
    var cname, cemail, cmessage;
    with (window.document.msgform) {
        cname = name;
        cemail = email;
        cmessage = message;
    }

    if (trim(cname.value) == '' || trim(cname.value) == defaultName) {
        alert('Please enter your name');
        cname.focus();
        return false;
    }
    else if (trim(cemail.value) == '' || trim(cemail.value) == defaultEmail) {
        alert('Please enter your email');
        cemail.focus();
        return false;
    }
    else if (!isEmail(trim(cemail.value))) {
        alert('Email address is not valid');
        cemail.focus();
        return false;
    }
    else if (trim(cmessage.value) == '' || trim(cmessage.value) == defaultMessage) {
        alert('Please enter a message');
        cmessage.focus();
        return false;
    }
    else {
        cname.value = trim(cname.value);
        cemail.value = trim(cemail.value);
        cmessage.value = trim(cmessage.value);
        return true;
    }
}

function trim(str) {
    return str.replace(/^\s+|\s+$/g, '');
}

function isEmail(str) {
    var regex = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;

    return regex.test(str);
}