display polyline as solid fill?

[Jeff de La Beaujardiere]

I downloaded a global coastline shapefile with feature type linestring.
I can feed it to UMN Mapserver and generate nice maps of the coastline.
However, I need the option to display the land (or the ocean) as a solid
color rather than an outline.

- Is there any way to do a solid fill if the FT is linestring?
- Would it work if were able to convert the FT to polygon?

Thanks for any info,
Jeff DLB