If I run 
nc -l 9903

[download]
And then run LWP and paste something like this into "nc" window 
HTTP/1.1 200 OK
Content-Length: 133

LNJKjadfkj
^C

[download]
I will get in 'lwp' window: 
GET -S -e http://localhost:9903/
GET http://localhost:9903/ --> 200 OK
Content-Length: 133
Client-Date: Thu, 30 May 2013 06:41:09 GMT
Client-Peer: 127.0.0.1:9903
Client-Response-Num: 1

LNJKjadfkj

[download]
So it's detected as success request. But tools like curl/wget report this as error/warning or even retry.
And according to RFC http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.4 Content-Length is priority over connecion close.
When a message-body is included with a message, the transfer-length of that body is determined by one of the following (in order of precedence):
...
3. If a Content-Length header field (section 14.13) is present, its decimal value in OCTETs represents both the entity-length and the transfer-length
...
5.By the server closing the connection.
Am I missing something?
UPD
So, not sure if this intended behaviour or no, so I reported a bug https://rt.cpan.org/Public/Bug/Display.html?id=85759

In reply to Should LWP warn about wrong Content-Length? by vsespb

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