fckstyles.xml not showing my option for li tag

i've got this as my fckstyles.xml file

<Styles>
   <Style name="Large Header" element="h1" />
   <Style name="Medium Header" element="h2" />
   <Style name="Small Header" element="h3" />
   <Style name="Paragraph" element="p" />
   <Style name="List Item Bullet" element="li">
        <Attribute name="class" value="bulletDisc" />
    </Style>
</Styles>

The List Item Bullet doesn't show up in FF 2.x (haven't tested other browsers yet). Is this a known bug or am i doing something wrong? I've also tried it with a ul element and still no joy. BUT if i change it to anything else it work A-OK.

jonese