use URI;
my $uri=URI->new("http://somedomain.com/cgi/register.cgi");
$uri->query_form(login=>"somelogin", id=>12345, email=>'foo@bar.com');
print "$uri\n";
__END__
http://somedomain.com/cgi/register.cgi?login=somelogin&id=12345&email=foo%40bar.com