# Gavin Andresen
# 2010-08-03 22:52:10
# https://bitcointalk.org/index.php?topic=689.msg7358#msg7358

@s{quotedtext}
@s{quotedtext}
Perl's LWP module definitely sets the Content-Length header.  I would've been surprised if it didn't, since it is required by HTTP 1.0 and the HTTP 1.1 spec says clients 'SHOULD' set it. @p{par}

After some struggle, I got the first @p{(link}JSON::RPC library@p{link)} at CPAN to work: @p{brk}

Code:
use JSON::RPC::Client; @p{brk}
use Data::Dumper; @p{par}

my $client = new JSON::RPC::Client; @p{par}

$client-@s{gt}ua-@s{gt}credentials( @p{brk}
   'localhost:8332', 'jsonrpc', 'my rpcusername' =@s{gt} 'my rpcpassword'   # Replace with real user/pass @p{brk}
    ); @p{brk}
my @foo = $client-@s{gt}ua-@s{gt}credentials('localhost:8332', 'jsonrpc'); @p{brk}
print "@foo\n"; @p{par}

my $uri = '@s{(link)}'; @p{brk}
my $obj = { @p{brk}
    method  =@s{gt} 'getinfo', @p{brk}
    params  =@s{gt} [], @p{brk}
 }; @p{par}

my $res = $client-@s{gt}call( $uri, $obj ); @p{par}

if($res){ @p{brk}
    if ($res-@s{gt}is_error) { @p{brk}
        print "Error : ", $res-@s{gt}error_message; @p{brk}
    } @p{brk}
    else { @p{brk}
        print Dumper($res-@s{gt}result); @p{brk}
    } @p{brk}
} @p{brk}
else { @p{brk}
    print $client-@s{gt}status_line; @p{brk}
} @p{brk}

The struggle was setting the realm to 'jsonrpc' (it is fussy about that).  I'll document that on the wiki. @p{par}