problem displaying XML in browser using Cgi

Hi I have a simple CGI program that takes data from a data source and posts
it
as XML format on the browser,  I have tested my program on IE and Mozilla
and they behave differently.  Sometimes XML format is displayed sometimes
just the data is displayed excluding the elements.

Here is a snippet of my code that displays the data:

sub displayInfo{
   my($state,$statename,$stationname,$station,%xmlHash) = @_;
   print <<__XML
<?xml version="1.0"?>
   <weather>
   <station stationId ="$station" stationName="$stationname" state="$state">
   <observationTime>$xmlHash{"observationTime"}</observationTime>
   <currentWeather>$xmlHash{"weather"}</currentWeather>
   <temprature>$xmlHash{"temprature"}</temprature>
   <wind>$xmlHash{"windMph"} mph from $xmlHash{"windDirection"}</wind>
   </station>
   </weather>
__XML
}


It seems that Mozilla is pretty strict on displaying the data in XML format.
For instance the following perl block:

   print <<__ERROR
<?xml version="1.0"?>
       <weather>
         <meta>
           <error>
           Incompatible Data.
           </error>
         </meta>
       </weather>
__ERROR

gets displayed as just:
Incompatible Data.

As if it were HTML.

If anyone has any ideas I would appreciate it.