in reply to 500 EOF when chunk header expected

I have met the same problem, and a solution was to add
BEGIN { $ENV{PERL_LWP_USE_HTTP_10} = 1; }
or examining LWP/UserAgent.pm
if ($ENV{PERL_LWP_USE_HTTP_10}) { require LWP::Protocol::http10; LWP::Protocol::implementor('http', 'LWP::Protocol::http10'); eval { require LWP::Protocol::https10; LWP::Protocol::implementor('https', 'LWP::Protocol::https10'); }; }
to add the lines enclosed in the if statement directly. Cheers.