Thank you for your help, i located the error.
The code
$request = new HTTP::Request(POST "http://www.abc.com/ChooseZone.aspx?
+type=A" , [
'__EVENTTARGET' => "rdlZone_0",
'__EVENTARGUMENT' => "",
'__VIEWSTATE' => "dDw0NzUyO",
'rdlZone' => "1",
] );
has been changed to
$request = new HTTP::Request('POST'=> "http://www.abc.com/ChooseZone.a
+spx?
+type=A" , [
'__EVENTTARGET' => "rdlZone_0",
'__EVENTARGUMENT' => "",
'__VIEWSTATE' => "dDw0NzUyO",
'rdlZone' => "1",
] );
It was a matter of changing POST to 'POST'=>
Thank you for your help