jsf 2.0 response already commented (ajax)

Question

overflow,

since yesterday I have for unknown reasons following problem:

i have a list of items, and when i delete one of them and let the page refresh by ajax, it stucks after the deletion-procedure and prints me following error:

Jul 28, 2013 3:54:42 PM org.apache.myfaces.context.servlet.ServletExternalContextImpl setResponseContentType SEVERE: Cannot set content type. Response already committed

the deletion code is called by:

public void deleteEntry(AjaxBehaviorEvent event){...} //runs fine

and the ajax part is:

<h:commandButton value="delete" onclick="closeDialog(deleteDlg);">
    <f:ajax event="click" execute="@form" render=":maintable" listener="#{updateEntryMetaDataBean.deleteEntry}"/>
</h:commandButton>

i don't really know why this error occurs, it seems like it only occurs on this specific page, on other pages with the same behaviour it runs fine.

my ajax-status hangs up and keeps running too:

    <!-- AJAX-STATUS INFO --> 
    <p:ajaxStatus style="width:64px;height:64px;position:fixed;right:5px;bottom:5px">  
        <f:facet name="start">
            <p:graphicImage value="resources/images/loading.gif" />  
        </f:facet>   

        <f:facet name="complete">  
            <h:outputText value="" />  
        </f:facet>  
    </p:ajaxStatus>

what can I do there?