Quick post this evening, because I'm stopping for the day. Just a troubleshooting tip for web services. We use the excellent Drupal Services module quite a lot for integration work. Take a look, if you don't know it:
http://drupal.org/project/services
Anyway, we always switch on the full security options, which are great for securing the API but stacked full of nasty gotchas. I had a new one today and I thought I'd share.
Part of building an authentication token for the Drupal Services module is adding in a timestamp. The code we normally use looks like this:
<?php