Description:
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Tried out pecl/oauth today to use with Twitter's APIs - works great for GET requests!

For POSTs, however (when OAUTH_AUTH_TYPE_FORM auth_type is used), Twitter's servers give a "417 Expectation Failed" error, since cURL sets the "Expect: 100-continue" request header for POSTs, which is rejected by Twitter. See <http://paininthetech.com/2008/12/29/php-curl-disable-100-continue-expectation>.

To fix this, can you set an empty Expect header while using cURL on line 570 of <http://cvs.php.net/viewvc.cgi/pecl/oauth/oauth.c?revision=1.21&view=markup>, please?

Thanks a lot!

Reproduce code:
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<?php
require('config.inc');
define('TWITTER_API_URL', 'http://twitter.com/statuses/update.xml');
try {
    /* initialize */
    $o = new OAuth(TWITTER_OAUTH_CONSUMER_KEY, TWITTER_OAUTH_CONSUMER_SECRET, OAUTH_SIG_METHOD_HMACSHA1, OAUTH_AUTH_TYPE_FORM);
    $request_token_info = unserialize(file_get_contents(TWITTER_OAUTH_RESPONSE_FILE)); // stored when we got the request token
    /* set our request token information for fetching the access token */
    $o->setToken($request_token_info["oauth_token"], $request_token_info["oauth_token_secret"]);
    $tweet = array('status' => urlencode('This tweet is courtesy of OAuth awesomeness.'));
    $status = $o->fetch(TWITTER_API_URL, $tweet);
    var_dump($status);
    $response_info = $o->getLastResponseInfo();
    var_dump($response_info);
    header("Content-Type: {$response_info["content_type"]}");
    echo $o->getLastResponse();
} catch(Exception $E) {
        echo "Error: [".$E->errorMessage."]<br>\n";
        echo "Response: [".$E->lastResponse."]<br>\n";
        exit;
}


Expected result:
----------------
Twitter status gets updated.

Actual result:
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HTTP status 417 Expectation Failed