Filter capabilities (DWidth)

[Miguel Gonçalves]

Hello,

I am using the filter interface of MapServer.
In the following request I want to get as results the cities in a range 
from the point -8.418000,41.539600.

<gml:Point><gml:coordinates>-8.418000,41.539600</gml:coordinates></gml:Point><Distance 
units='m'>1</Distance>
<Filter>
    <DWithin>
        <gml:Point>
        <gml:coordinates>-8.418000,41.539600</gml:coordinates>
        </gml:Point>
        <Distance units='m'> 0.9 </Distance>
    </DWithin>
</Filter>

The problem is that I have no idea how big the range is, i.e.,
 in the fragment <Distance units='m'> 0.9 </Distance> I do not know in 
which units the distance is being mesured.
Can you help me?
Best regards.


Miguel