It seems that the server only reads the first line of the request from the client, and then sends out the response. For example:

shahar.e@wintergreen tests $ telnet localhost 8888
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
GET /testSimpleRequests.php HTTP/1.1
HTTP/1.1 200 OK
Content-type: text/html
X-powered-by:  PHP/5.1.6-pl8-gentoo

SuccessConnection closed by foreign host.

I only typed the "GET" line - and when I hit enter I got the response. Normally, the server should wait for a blank line (IE two consecutive CRLFs) before it finishes reading.

This prevents sending HTTP headers (and cookies) as well as message body (IE POST data).

For comparison, this is a request for the same file (docroot is different but it's the same script) from Apache 2.0.x:

shahar.e@wintergreen tests $ telnet localhost 80
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
GET /Framework/tests/testSimpleRequests.php HTTP/1.1
Host: localhost
Connection: close

HTTP/1.1 200 OK
Date: Fri, 10 Nov 2006 21:09:01 GMT
Server: Apache
X-Powered-By: PHP/5.1.6-pl8-gentoo
Content-Length: 7
Connection: close
Content-Type: text/html

SuccessConnection closed by foreign host.

Here, I was able to type the "Host" and "Connection" headers, and then a blank line, and only then I got the response.