<b:dataTable value="#{misServCtrl.listaPostulaCliente}" var="p" lang="es">
  <b:dataTableColumn value="#{p.idPostulacion}" label="Número" />
  <b:dataTableColumn label="Soportes">
    <c:if test="#{misServCtrl.listaImagenes != null}">
        <c:forEach items="#{misServCtrl.listaImagenes}" var="listImg">
            <c:forEach items="#{listImg}" var="img">
                <p:lightBox>
                    <h:outputLink value="img_soporte/#{img.imagenNombre}" title="Soporte 1">
                        <b:button value="Soporte 1" look="default" icon-awesome="picture-o" />
                    </h:outputLink>
                    <h:outputLink value="img_soporte/#{img.imagenNombre}" title="Soporte 2">
                        <b:button value="Soporte 2" look="default" icon-awesome="picture-o" />
                    </h:outputLink>
                    <h:outputLink value="img_soporte/#{img.imagenNombre}" title="Soporte 3">
                        <b:button value="Soporte 3" look="default" icon-awesome="picture-o" />
                    </h:outputLink>
                </p:lightBox>
            </c:forEach>
        </c:forEach>
    </c:if>
  </b:dataTableColumn>

<c:forEach items="#{misServCtrl.listaImagenes}" var="img">
                <p:lightBox>
                    <h:outputLink value="img_soporte/#{img.imagenNombre}" title="Soporte 1">
                        <b:button value="Soporte 1" look="default" icon-awesome="picture-o" />
                    </h:outputLink>
                   ...
                </p:lightBox>
        </c:forEach>

...
xmlns:ui="http://java.sun.com/jsf/facelets"...

<b:dataTable value="#{misServCtrl.listaPostulaCliente}" var="p" lang="es">
  <b:dataTableColumn value="#{p.idPostulacion}" label="Número" />
  <b:dataTableColumn label="Soportes">

        <ui:repeat var="img" rendered="#{not empty misServCtrl.listaImagenes}" value="#{misServCtrl.listaImagenes}" >

                <p:lightBox>
                    <h:outputLink value="img_soporte/#{img.imagenNombre}" title="Soporte 1">
                        <b:button value="Soporte 1" look="default" icon-awesome="picture-o" />
                    </h:outputLink>
                    <h:outputLink value="img_soporte/#{img.imagenNombre}" title="Soporte 2">
                        <b:button value="Soporte 2" look="default" icon-awesome="picture-o" />
                    </h:outputLink>
                    <h:outputLink value="img_soporte/#{img.imagenNombre}" title="Soporte 3">
                        <b:button value="Soporte 3" look="default" icon-awesome="picture-o" />
                    </h:outputLink>
                </p:lightBox>

        </ui:repeat>
  </b:dataTableColumn>