I added a h:dataTable inside the modalPanel and the h:dataTable displays fine...

<!DOCTYPE composition PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<ui:composition xmlns="http://www.w3.org/1999/xhtml"
 xmlns:s="http://jboss.com/products/seam/taglib"
 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.ajax4jsf.org/rich"
 xmlns:a4j="https://ajax4jsf.dev.java.net/ajax"
 xmlns:c="http://java.sun.com/jstl/core"
 template="layout/template.xhtml">



<ui:define name="body">

 <script type="text/javascript">
 function showPanel() {
 Richfaces.showModalPanel('mpNote',{width:450, top:200});
 }
 </script>


 <rich:modalPanel id="mpNote"> <!-- minHeight="200" minWidth="450" height="500" width="500" zindex="2000"> -->
 <h:form>

 <rich:scrollableDataTable value="#{noteAction.getNoteLogList()}" var="myRow" rows="10" height="50px" width="300px">

 <rich:column>
 <f:facet name="header">NoteText</f:facet>
 <h:outputText value="#{myRow.noteText}"/>
 </rich:column>

 <rich:column>
 <f:facet name="header">TimeStamp</f:facet>
 <h:outputText value="#{myRow.timeStamp}"/>
 </rich:column>

 </rich:scrollableDataTable>

 <rich:dataTable value="#{noteAction.getNoteLogList()}" var="myRow">

 <rich:column>
 <f:facet name="header">NoteText</f:facet>
 <h:outputText value="#{myRow.noteText}"/>
 </rich:column>

 <rich:column>
 <f:facet name="header">TimeStamp</f:facet>
 <h:outputText value="#{myRow.timeStamp}"/>
 </rich:column>

 </rich:dataTable>
 </h:form>
 </rich:modalPanel>

 <h:commandButton value="show" onclick="showPanel();"/>
 <BR/><BR/>
 <h:form>

 <rich:scrollableDataTable value="#{noteAction.getNoteLogList()}" var="myRow" rows="10" height="50px" width="300px">

 <rich:column>
 <f:facet name="header">NoteText</f:facet>
 <h:outputText value="#{myRow.noteText}"/>
 </rich:column>

 <rich:column>
 <f:facet name="header">TimeStamp</f:facet>
 <h:outputText value="#{myRow.timeStamp}"/>
 </rich:column>

 </rich:scrollableDataTable>
 </h:form>

</ui:define>
</ui:composition>

sorry I meant added rich:dataTable...