I have a custom tag that is composed by a <h:outputLabel /> + <h:inputText />. I need the maxlength to be optional. The problem is that when I use <f:attribute /> I get a class cast exception.

Tag:

<ui:composition
 xmlns:h="http://java.sun.com/jsf/html"
 xmlns:c="http://java.sun.com/jstl/core"
 xmlns:f="http://java.sun.com/jsf/core"
 xmlns:ui="http://java.sun.com/jsf/facelets"
>
 <h:outputLabel value="#{label}" />
 <h:inputText
 label="#{label}"
 value="#{value}"
 >
 <c:if test="#{! empty maxlength}">
 <f:attribute
 name="maxlength"
 value="#{maxlength}"
 />
 </c:if>
 <ui:insert />
 </h:inputText>
</ui:composition>

java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Integer