I'm using Seam 2.0.GA, RichFaces 3.2.1.GA in Tomcat 6. I have a rich:dropDownMenu in a rich:dataGrid as follows:

 <a:outputPanel id="prodPanel">
 <rich:dataGrid columns="2" elements="6" value="#{products}" var="product" rendered="#{products.rowCount>0}" style="float:left;width:930px">
 <rich:panel style="height:375px">
 <f:facet name="header"><h:outputText value="#{product.name}"/></f:facet>
 <rich:dropDownMenu value="More actions..." style="width:100px" rendered="#{identity.loggedIn}">
 <rich:menuItem submitMode="none" icon="images/edit.png">
 <s:link value="Edit" action="#{productManager.createObject}" >
 <f:param name="prodId" value="#{product.id}"/>
 </s:link>
 </rich:menuItem>
 </rich:dropDownMenu>
 ......
 </rich:dataGrid>
</a:outputPanel>

As can be seen from the code the dropdown menu can only be seen if the user is logged in to allow editing of an entity. This dropDown menu appears alright when a user is logged in.

The problem is that passing the mouse over the drop down menu immediately causes the whole panel grid to be distorted, especially if it hasn't reached its limit of 6 items in a grid. And this only happens if
the user is logged inthe browser being used to view the page is Firefox

Testing in Internet Explorer 7 does not produce this behaviour at all, and in Firefox only if the dropDownMenu is showing i.e. a user is logged in.

I'm thinking this is a browser issue. Is there anything i can do to force Firefox not to try "resizing" or whatever it does but stick to the dimensions I give?