I found the answer too:
It results that (I didn't know) seblod needs mootools core to save a form, and it needs a script for submit it.
So I had to add mootools libraries (too bad, too much .js in my template, and hard to minify everything and put it in) and the inline script to my form
<script type="text/javascript">
JCck.Core.submit = function(task) {
var formulario = jQuery("#seblod_form");
if (formulario.validationEngine("validate",task) === true) {
if (formulario.isStillReady() === true) {
formulario.find("input[name='config[unique]']").val("seblod_form_user");
Joomla.submitform("save", document.getElementById("seblod_form"));
}
}
}
</script>