Iam modifying the data from bucket brigade (i.e. replacing customer name with my own hardcoded name (where $h is filter data),

if ($filter->seen_eos)
{
$h =~ s/custlastname/ccc/g;
$h = $h . "&custlastname=XXtestnameXX";
}

I re-define the 'Content Length' as well,

my $len = length $h;
$filter->r->headers_out->set('Content-Length', $len);

$h is passed to a proxy.

But after doing all this, the value of 'custlastname' is being passed as blank to the remote server.

Any suggestions?????????