I got a problem with the toolbar property in the rich text field. On the first load everything looks as expected, but after a partial refresh you can see all buttons in the richtext editor. It seems that you don't get the problem when you use slim, medium, large instead.
I use a Domino Server Version 9.0.1 FP3
Here is an example:
<xp:button value="Label" id="button1">
<xp:eventHandler event="onclick" submit="true"
refreshMode="partial" refreshId="inputRichText1">
</xp:eventHandler>
</xp:button>
<xp:inputRichText id="inputRichText1">
<xp:this.dojoAttributes>
<xp:dojoAttribute name="toolbar">
<xp:this.value><![CDATA[[['Format']]]]></xp:this.value>
</xp:dojoAttribute>
</xp:this.dojoAttributes>
</xp:inputRichText>