Fórum Atualizar input do form conforme alterações de outro input. #479192

<form  class="fonte_padrao" id="form1" name="form1" method="post" action="enviarEmail.php?id=<?php echo $idveiculo ?>">
<table width="425" border="0" align="center" cellpadding="0" cellspacing="5">
<tr>
		<td align="left">Data de Retirada: <br> <span id="sprytextfield12"><input  type="text" name="datar" id="datar" class="data" /><span class="textfieldRequiredState"></span></span></td>
		<td align="left">Data de Entrega:  <br> <span id="sprytextfield13"><input  type="text" name="datae" id="datae" class="data" /><span class="textfieldRequiredState"></span></span></td>
		<td align="left">Total: <br> <span id="sprytextfield14"><input  type="text" name="total" id="total" value="<?php echo $row['vlr_diaria']; ?>" /><span class="textfieldRequiredState"></span></span></td>
	  </tr>
      <tr>
         <td>
        <input type="submit" value="Reservar" class="button1" />
        <input type="reset" value="Limpar" class="button1"/></td>
      </tr>
    </table>