Struts2 - How to create a <s:form> for each row in <display:table>

I was trying to show a displaytag table and I wish to map each row on a different s:form.
Each row show all the attributes of my System object and I wish to choose one row and act on the related object.
I tryed to put multiple display:column in one form, but when I load the JSP, I don't find any form tag.

Any suggestion?

My code:

<display:table name="${systemList}" uid="row" pagesize="20" sort="list" requestURI="" >
 
 <display:column title="System ID"       property="systemID"                     sortable="true" />
 
             ... other columns ...
 
 <s:form action="provision.action" method="post" name="provisionForm%{#attr.row.systemID}">
 
 <display:column title="IP" >
     <s:textfield name="systemList[%{#attr.row_rowNum - 1}].ip"  />
 </display:column>
 
 <display:column>
     <s:submit type="image" src='image.png' name='submit' />
 </display:column>
 </s:form>
 
 </display:table>
 

Thanks in advance

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