I am trying to set up the PHP API for CloudWatch found here. There are 2 samples with the library and I have managed to get the first (ListMetricsSample.php) to display a list of the metrics available for my running instances in Europe. As far as I can see though this just lists the metrics, there are no values for the metrics given in this sample. So I assume I need to try the other sample (GetMetricStatisticsSample.php) but when I configure this to connect in the same way as the previous sample it returns an Internal Error Response Status Code:400
Anyone know what this means and how to fix it?
cheers