Throw exception "Google_IO_Exception" with the message "HTTP error: cannot connect

Question

Throw exception "Google_IO_Exception" with the message "HTTP error: cannot connect

I have a task (request) running some php code that retrieves data from gmail mailboxes. It works fine until the last Friday (April 10, 2015), and now I get this error log:

E 11:58:26.094 2015-04-15  200   3.38 KB   14.2s /code.php
  0.1.0.2 - - [15/Apr/2015:07:58:26 -0700] "POST /code.php HTTP/1.1" 200 3462 "https://xxxxxxxxx.appspot.com/start.php?email=test@email.com" "AppEngine-Google; (+http://code.google.com/appengine)" "mailroof-test.appspot.com" ms=14201 cpu_ms=407 cpm_usd=0.001221 queue_name=worker task_name=13657588804765054031 instance=00c61b117c031f6c5ded2e3d1653abac0f4b87fa app_engine_release=1.9.19
    E 11:58:26.088 PHP Fatal error:  Uncaught exception 'Google_IO_Exception' with message 'HTTP Error: Unable to connect: 'fopen(https://www.googleapis.com/gmail/v1/users/me/messages?maxResults=100&labelIds=INBOX&pageToken=12866883594511227777): failed to open stream: Unsupported SSL context options are set. The following options are present, but have been ignored: cafile
      Fetch error'' in /base/data/home/apps/xxxxxxxxx/1.383623356139435513/google-api-php-client/src/Google/IO/Stream.php:140
      Stack trace:
      #0 /base/data/home/apps/xxxxxxxxx/1.383623356139435513/google-api-php-client/src/Google/IO/Abstract.php(133): Google_IO_Stream->executeRequest(Object(Google_Http_Request))
      #1 /base/data/home/apps/xxxxxxxxx/1.383623356139435513/google-api-php-client/src/Google/Http/REST.php(61): Google_IO_Abstract->makeRequest(Object(Google_Http_Request))
      #2 [internal function]: Google_Http_REST::doExecute(Object(Google_Client), Object(Google_Http_Request))
      #3 /base/data/home/apps/xxxxxxxxx/1.383623356139435513/google-api-php-client/src/Goo in /base/data/home/apps/xxxxxxxxx/1.383623356139435513/google-api-php-client/src/Google/IO/Stream.php on line 140