See http://search.cpan.org/perldoc?LWP::Simple; you would use something like:

use LWP::Simple;
my $url = "http://SERVERIP/httppush/http.aspx?text=TEXTMESSAGE&source=
+SOURCENUMBER&desti nation=DESTINATIONNUMBER&username=USERNAME&passwor
+d=PASSWORD&datacoding=1";
get ( $url );
[download]