can you use a perl script?
%form = ( key1 => "key1value", # whatever you want to post goes here, fairly straightforward.
key2 => "key2value",
key3 => "key3value" );
$ua = new LWP::UserAgent;
my $curl = url("http:");
my $req = new HTTP::Request 'POST',
"http://www.singtel-mobile.com/products_services/online_services/sms.html"; # your url here
print $ua->request($req)->as_string; #this will print the results, comment it out if you feel it slows things down too much.