function clear_field(field){

   

	if (field.value==field.defaultValue)    {    



	field.value=''    }

}



function check_field(field){



    if (field.value=='' ||

    field.value==' ')    {



        field.value=field.defaultValue    }

}





function over(){

	document.getElementById("enviar").style.background = "url(imagens/botao.png) no-repeat top right";

}

function out(){

	document.getElementById("enviar").style.background = "url(imagens/botao.png) no-repeat top left";

}