doh...
> <registerIndexer
> for=".interfaces.IMyContent"
> provides=".interfaces.ISomeCalledInterface"
> factory=".SomeCallabelAdapter"
> permission="zope2.Public"
> />
>
could be simpler (no need for factory or permission), just:
<registerIndexAdapter
for=".interfaces.IMyContent"
index=".interfaces.ISomeCalledInterface"
/>
-w