The issue was solved nesting each table inside a panelGrid (no idea whether this should be the strictly correct approach but it worked):
<?xml version="1.0" encoding="ISO-8859-1" standalone="yes" ?>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:rich="http://richfaces.org/rich"
xmlns:c="http://java.sun.com/jstl/core">
<ui:composition template="layouts/template.jsf">
<ui:define name="body">
<h3>#{msg.homepageCaption1}</h3>
<h:form id="form">
<h:panelGrid columnClasses="acent">
<rich:dataTable value="#{HomepageBean.firstTable}"
var="tOne" id="tableOne" rows="5">
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.firstColumn}" />
</f:facet>
<h:outputText value="#{tOne.firstColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.secondColumn}" />
</f:facet>
<h:outputText value="#{tOne.secondColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.thirdColumn}" />
</f:facet>
<h:outputText value="This is an String" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.fourthColumn}" />
</f:facet>
<h:outputText value="#{tOne.fourthColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.fifthColumn}" />
</f:facet>
<h:outputText value="#{tOne.fifthColumn}" />
</rich:column>
</rich:dataTable>
<rich:dataScroller for="tableOne"
pageIndexVar="#{HomepageBean.firstTablePage}"
ajaxSingle="false">
<f:facet name="previous">
<h:outputText value="<" />
</f:facet>
<f:facet name="next">
<h:outputText value=">" />
</f:facet>
<f:facet name="fastrewind">
<h:outputText value="<<" />
</f:facet>
<f:facet name="fastforward">
<h:outputText value=">>" />
</f:facet>
</rich:dataScroller>
</h:panelGrid>
<h:panelGrid columnClasses="acent">
<h3>#{msg.homepageCaption2}</h3>
<rich:dataTable
value="#{HomepageBean.secondTable}" var="tTwo"
id="tableTwo" rows="5">
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.firstColumn}" />
</f:facet>
<h:outputText value="#{tTwo.firstColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.secondColumn}" />
</f:facet>
<h:outputText value="#{tTwo.secondColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.thirdColumn}" />
</f:facet>
<h:outputText value="This is an string" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.fourthColumn}" />
</f:facet>
<h:outputText value="#{tTwo.fourthColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.fifthColumn}" />
</f:facet>
<h:outputText value="#{tTwo.fifthColumn}" />
</rich:column>
</rich:dataTable>
<rich:dataScroller for="tableTwo"
pageIndexVar="#{HomepageBean.secondTablePage}"
ajaxSingle="false">
<f:facet name="previous">
<h:outputText value="<" />
</f:facet>
<f:facet name="next">
<h:outputText value=">" />
</f:facet>
<f:facet name="fastrewind">
<h:outputText value="<<" />
</f:facet>
<f:facet name="fastforward">
<h:outputText value=">>" />
</f:facet>
</rich:dataScroller>
</h:panelGrid>
<h:panelGrid columnClasses="acent">
<h3>#{msg.homepageCaption3}</h3>
<rich:dataTable
value="#{homepageBean.thirdTable}" var="tThree"
id="tableThree" rows="5">
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.firstColumn}" />
</f:facet>
<h:outputText value="#{tThree.firstColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.secondColumn}" />
</f:facet>
<h:outputText value="#{tThree.secondColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.thirdColumn}" />
</f:facet>
<h:outputText value="This is an string" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.fourthColumn}" />
</f:facet>
<h:outputText value="#{tThree.fourthColumn}" />
</rich:column>
<rich:column>
<f:facet name="header">
<h:outputText value="#{msg.fifthColumn}" />
</f:facet>
<h:outputText value="#{tThree.fifthColumn}" />
</rich:column>
</rich:dataTable>
<rich:dataScroller for="tableThree"
pageIndexVar="#{homepageBean.thirdTablePage}"
ajaxSingle="false">
<f:facet name="previous">
<h:outputText value="<" />
</f:facet>
<f:facet name="next">
<h:outputText value=">" />
</f:facet>
<f:facet name="fastrewind">
<h:outputText value="<<" />
</f:facet>
<f:facet name="fastforward">
<h:outputText value=">>" />
</f:facet>
</rich:dataScroller>
</h:panelGrid>
</h:form>
</ui:define>
</ui:composition>
</html>