String.prototype.trim = function(){
	    return this.replace(/^( *)|( *)$/g,"");
	}
	
function vForm()
	{	
		if (!vEmail(document.forms[0].email))
		{
			return false;
		}
		
		for( var i = 0 ; i < document.forms[0].length; i++ )
		  {
		    switch( document.forms[0].elements[ i ].type )
		    {
		  	case 'text':
		     if( document.forms[0].elements[ i ].value.trim() == '' && document.forms[0].elements[ i ].getAttribute("obrigatorio") == 1)
			    {	
				  	alert('O campo ' + document.forms[0].elements[ i ].getAttribute("descricao") + ' é obrigatório!.');
					document.forms[0].elements[ i ].focus();
					return false;
				}	
		   }
		}
		
		return true;		
	}
	
function vEmail(obj)
{	
	expressao = /^[\w!#$%&'*+\/=?^`{|}~-]+(\.[\w!#$%&amp;'*+\/=?^`{|}~-]+)*@(([\w-]+\.)+[A-Za-z]{2,6}|\[\d{1,3}(\.\d{1,3}){3}\])|[\w-]+(\.[\w-]+)*@(([\w-]{2,63}\.)+[A-Za-z]{2,6}|\[\d{1,3}(\.\d{1,3}){3}\])|[\w-]+(\.[\w-]+)*@(([A-Za-z\d][A-Za-z\d-]{0,61}[A-Za-z\d]\.)+[A-Za-z]{2,6}|\[\d{1,3}(\.\d{1,3}){3}\])$/;

	valido = expressao.test(obj.value)

	if (valido == false)
	{
		alert('por favor, digite um email válido');
		obj.value = "";
		obj.focus();
		return false;
	}
	
	return true;
}