function validEmailAddress(email)
{
		invalidChars = " /:,;~"
		if (email == "") 
		{
			return (false);
		}
		for (i=0; i<invalidChars.length; i++) 
		{
			badChar = invalidChars.charAt(i)
			if (email.indexOf(badChar,0) != -1) 
			{
				return (false);
			}
		}
		atPos = email.indexOf("@",1)
		if (atPos == -1) 
		{
			return (false);
		}
		if (email.indexOf("@",atPos+1) != -1) 
		{
			return (false);
		}
		periodPos = email.indexOf(".",atPos)
		if (periodPos == -1) 
		{
			return (false);
		}
		if (periodPos+3 > email.length)	
		{
			return (false);
		}
			
		return (true);
}

// for change password page
function ch_pass_validate(obj)
{
	if(obj.old_pass.value=='')
	{		
		alert(obj.old_pass.getAttribute("mymsg"));
		obj.old_pass.focus();
		return false;
	}
	if(obj.new_pass.value=='')
	{		
		alert(obj.new_pass.getAttribute("mymsg"));
		obj.new_pass.focus();
		return false;
	}
	if(obj.retype_pass.value=='')
	{		
		alert(obj.retype_pass.getAttribute("mymsg"));
		obj.retype_pass.focus();
		return false;
	}
	else
	{
		if(obj.retype_pass.value!=obj.new_pass.value)
		{
			alert(obj.retype_pass.getAttribute("equalmsg"));
			obj.new_pass.focus();
			return false;
		}
	}
}


// for change email page
function ch_email_validate(obj)
{
	if(obj.username.value=='')
	{		
		alert(obj.username.getAttribute("mymsg"));
		obj.username.focus();
		return false;
	}
	if(obj.old_email.value=='')
	{		
		alert(obj.old_email.getAttribute("mymsg"));
		obj.old_email.focus();
		return false;
	}else if(!validEmailAddress(obj.old_email.value))
	{		
		alert(obj.old_email.getAttribute("validmsg"));
		obj.old_email.focus();
		return false;
	}
	if(obj.new_email.value=='')
	{		
		alert(obj.new_email.getAttribute("mymsg"));
		obj.new_email.focus();
		return false;
	}else if(!validEmailAddress(obj.new_email.value))
	{		
		alert(obj.new_email.getAttribute("validmsg"));
		obj.new_email.focus();
		return false;
	}	
}


//check all checkboxes.
function check_all(objForm)
{
	len = objForm.elements.length;
	var i=0;
	for( i=0 ; i<len ; i++){
		if (objForm.elements[i].type=='checkbox')
			objForm.elements[i].checked=true;
	}
	
}

//uncheck all checkboxes.
function uncheck_all(objForm)
{
	len = objForm.elements.length;
	var i=0;
	for( i=0 ; i<len ; i++){
		if (objForm.elements[i].type=='checkbox')
			objForm.elements[i].checked=false;
	}
	
}