I accomplished this without using the DynaActionForm. Its somewhat a crude way but it works. When stuck with constraints what is one to do?
Here is an example, in the JSP I have coded the form element: <input id="firstName<c:out value='${bnfIndex}'/>" type="text" name="beneficiaries[<c:out value='${bnfIndex}'/>].firstName" value="<c:out value='${beneficiary.firstName}'/>" size="15" maxlength="24"> Once rendered in the HTML: <input id="firstName0" type="text" name="beneficiaries[0].firstName" value="Joe" size="15" maxlength="24"> In the form bean: private List beneficiaries = new ArrayList(); public BeneficiaryVO getBeneficiaries(int index) { while (index >= beneficiaries.size()) { beneficiaries.add(new BeneficiaryVO()); } return (BeneficiaryVO) beneficiaries.get(index); } HTH, Glenn