This should work with a gateway, this is working code with some modified names. 

my $gsRemoteMachine = "ftp.site.com";
my $gsRemoteDir     = "/";
my $gsFtpId         = "username";
my $gsFtpPwd        = "password";
my $gsGateMachine   = "gateway.site.com";     # ftp gateway
my $gsGateConnect   = "\@$gsRemoteMachine ";  # remote machine connect
+id for gateway
my $gsRemoteMachine = $gsGateMachine;     
my $gsFeedsDir      = "/mypath/";
my $gsFeedFile       = "myfile";


system("ftp -n $RemoteMachine <<EOF> $StatusFile 2>&1\n\nuser $gsFtpId
$gsGateConnect $gsFtpPwd\nverbose\n$gsFtpMode\nput $gsFeedsDir$gsFeed
File $gsRemoteDir$gsFeedFile\nclose\nbye\nEOF");