http://struts.apache.org/faqs/indexedprops.html
Check those links in case you have an indexed property (like an array or list). It is very useful when you have a table that you want struts to link their properties automatically to the form.
In my case, it is a list (java.util.List) of item beans in the form that is iterated in the JSP, like this:
<logic:iterate id="items" name="orderEditForm" property="items">
<html:text name="items" indexed="true" property="product"/>
<html:text name="items" indexed="true" property="quantity"/>
<html:text name="items" indexed="true" property="amount"'/>
</logic:iterate>
This "items" property is defined in the orderEditForm as a List