Hi, I'm having some trouble with transparency layers appear/disappear. I'm working with MapServer and Openlayers... I want two layers to overlay but when I choose to show one the other one hides... Here is some  of my code.... Thanks for the help :)<br>
<br>Mapserver File:<br><br>MAP<br>  size 800  600<br>  imagetype 'gif'<br>  TRANSPARENT ON<br>  imagecolor 0 0 255<br>  extent -180 -90 180 90<br>  SYMBOLSET "symbols"<br>  PROJECTION<br>    "init=epsg:4269"<br>
  END<br><br>  WEB<br>    IMAGEPATH "/var/www/apache2-default/gis_tests/tmp/"<br>    IMAGEURL "/apache2-default/gis_tests/tmp/"<br>    TEMPLATE "empty.html"<br><br>    metadata<br>      wms_title "us_states"<br>
      wms_srs "EPSG:4269"<br>    end<br>  end<br><br><br>_______<br><br>OPenlayers:<br><br>             layer = new OpenLayers.Layer.MapServer( "Estados unidos",<br>                      "<a href="http://192.168.1.100/cgi-bin/mapserv?map=us_states.map">http://192.168.1.100/cgi-bin/mapserv?map=us_states.map</a>",<br>
                      {layers: 'us_states', 'format':'image/png'});<br>             roads = new OpenLayers.Layer.MapServer( "Roads",<br>                      "<a href="http://192.168.1.100/cgi-bin/mapserv?map=us_states.map">http://192.168.1.100/cgi-bin/mapserv?map=us_states.map</a>",<br>
                      {layers: 'us_roads',transparent: 'true',  'format':'image/png'}, {isBaseLayer:false});<br>             gps = new OpenLayers.Layer.MapServer( "GPS",<br>                      "<a href="http://192.168.1.100/cgi-bin/mapserv?map=us_states.map">http://192.168.1.100/cgi-bin/mapserv?map=us_states.map</a>",<br>
                      {layers: 'gps_points', transparent: 'true', 'format':'image/png' }, {isBaseLayer:false});<br><br>            roads.setVisibility(false);<br>            gps.setVisibility(false);<br>
<br clear="all"><br>-- <br>Rafael Chacon,<br><br>"El hombre es la medida de todas las cosas". Protagoras<br>