You're doing weird things with the low-level parts of the LWP API. This is much shorter and actually working as intended (takes care of assembling and encoding the request the correct way): 
use LWP::UserAgent qw();
my $response = LWP::UserAgent
    ->new
    ->post(
        $buildManagerUrl,
        {
            action => $action,
            params => $callParamsJson,
        }
    );

[download]

In reply to Re: HTTP Data Being Changed by Anonymous Monk
in thread HTTP Data Being Changed by dlwester

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