I'm trying to move my kml styles to an external document for use with OpenLayers. The styles work when they are included directly in the kml file.

At first I thought I could use straight kml for this with the styleUrl tag:

```
<styleUrl>http://localhost/map.kml#myIcon</styleUrl>

```

However, when I try to do that, the map.kml file never gets requested, and the markers don't show up. I've verified that the styleUrl url works.

I'm loading my kml using:

```
new OpenLayers.Layer.GML('Name', 'kml_path', {
  format: OpenLayers.Format.KML,
    formatOptions: {
      extractStyles: true,
      extractAttributes: true
    },
    projection: map.displayProjection
});

```

There are some tantalizing options called 'styles' and 'styleBaseUrl' in the OpenLayers.Format.KML API, but I cannot find any documentation about what they are for or how to use them. Does anyone have any experience with these?