don't see a reason why it shouldn't work for a relation
for a relation you will need an entry in the relations file to copy tags to the lines and then process the rules for the lines

an example I have been playing with for highways. a new tag route_ref is defined from the relation and applied to the line. in the line style you can use the usual syntax to use this tag.
you can also use the usual tags. I just kept it on a special tag name to have the ref from the way and from the relation in different tags for flexible use

# style/relations
type=route & route=road { apply { 
           add route_ref='${network} ${ref} ${direction}'; 
           add  route_ref='${network} ${ref}'; 
}}

# style/lines
highway=* {name '${route_name}' | '${route_ref} ${name}' | '${ref} ${name}' | '$
{name}'| '${ref}'  }


On Mon, Aug 3, 2009 at 4:30 PM, maning sambale <emmanuel.sambale@gmail.com> wrote:
Marco,

Does this work as a relation?

> #boundaries
>
> boundary=administrative & admin_level<3 [0x1e resolution 14]
> boundary=administrative & admin_level<5 [0x1d resolution 16]
> boundary=administrative & admin_level<7 [0x1d resolution 20]
> boundary=administrative                 [0x1c resolution 22]
> boundary=political                      [0x1c resolution 22]
> boundary=national                       [0x1e resolution 14]
>
> It looks nice for Italy.
>
> Ciao, Marco.
>
>>
>> On 8/3/09, Lambertus <osm@na1400.info>
>> wrote:
>> > It appears that very low level administrative
>> boundaries are rendered
>> > quite prominently using the default Mkgmap style. An
>> example is shown
>> > here: http://forum.openstreetmap.org/viewtopic.php?pid=31404#p31404
>> >
>> > What are the options to reduce the visibility of those
>> boundaries?
>> > _______________________________________________
>> > mkgmap-dev mailing list
>> > mkgmap-dev@lists.mkgmap.org.uk
>> > http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
>> >
>>
>>
>> --
>> cheers,
>> maning
>> ------------------------------------------------------
>> "Freedom is still the most radical idea of all" -N.Branden
>> wiki: http://esambale.wikispaces.com/
>> blog: http://epsg4253.wordpress.com/
>> ------------------------------------------------------
>> _______________________________________________
>> mkgmap-dev mailing list
>> mkgmap-dev@lists.mkgmap.org.uk
>> http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
>>
>
>
>
> _______________________________________________
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> mkgmap-dev@lists.mkgmap.org.uk
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>



--
cheers,
maning
------------------------------------------------------
"Freedom is still the most radical idea of all" -N.Branden
wiki: http://esambale.wikispaces.com/
blog: http://epsg4253.wordpress.com/
------------------------------------------------------
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