I'm not able to reproduce your error. Do you have any sample code to share?
What PHP version are you running?
This test works fine for me:
//PHP API Client Lib is available here: https://github.com/ryanjarvinen/eventbrite.php
include "Eventbrite.php";
//Authorization tokens are outlined here:
// http://developer.eventbrite.com/doc/authorization/
$eb = new Eventbrite(array('app_key'=>'YOUR_APPLICATION_KEY','user_key'=>'YOUR_USER_KEY'));
try{
//Docs on how to use the API's event_new method are located here:
// http://developer.eventbrite.com/doc/events/event_new/
$response = $eb->event_new(array('title'=>'test event_new','start_date'=>'2012-12-12 12:00:00','end_date'=>'2012-12-12 12:12:12'));
print "The new event_id is: {$response->process->id}";
}catch( Exception $e){
var_dump($e);
}
There are a few more PHP-specific usage notes available on github.
Most of the general information about authentication tokens, as well as specifics on input and output parameters per API method, should be available on http://developer.eventbrite.com/