selectManyCheckbox: I can't visualize pre selected checkbox

[Claudio Pioggia]

Hi, I've a problem with the tag selectManyCheckbox in a JBoss Seam's context, this is my code:

<a:outputPanel id="ins_groups_panel">
<h:selectManyCheckbox id="groups" value="#{controller.page.groups}" layout="pageDirection" size="1" onclick="selectAllGroups(this);">
<f:selectItems value="#{controller.page.checkboxesGroups}" />

</h:selectManyCheckbox>
</a:outputPanel>

When I click this button, my action fill the list related to the selectManyCheckbox with the the values that must be pre-selected.

<a:commandButton id="editPeriod"
styleClass="rounded {transparent}"
action="#{controller.doEdit}"
reRender="confPeriodForm,panelInsertPeriods,ins_groups_panel"
onclick="if(false) {return false;}"
image="/images/database_edit.png" >
<a:actionparam name="idPeriod" value="#{periods.code}" assignTo="{controller.page.idPeriodToEdit}" />

</a:commandButton>





The selected checkbox setted in the server side application remain unchecked, the field groups is implemented with an ArrayList<String> in the page. If I print that list in the page I can see it correctly valued, so, I think the server side is correct. Someone can help me? (Sorry for my English)