Projection with Mapserver & PRJ

[Brian Peschel]

Does MapServer use PRJ files?  I need to do some projections with shape
files.  All of my shape files sets have prj files (ie town.shp, town.shx,
town.dbf, town.prj).  If I setup a map level projection like:
  PROJECTION
    "init=epsg:4326"
  END

do I need to setup a layer level projection also?  Or will MapServer read
the PRJ files and do the conversion on the fly for me?  I am struggling to
understand how to convert a PRJ file into the PROJ.4 parameters like:
  PROJECTION
      "proj=laea"
      "ellps=clrk66"
      "lat_0=45"
      "lon_0=-100"
  END
(which is from the tutorial, and is not the settings I need).

Any help in this would be appreciated...

Brian