This problem seems to have been discussed in the past everywhere on google and here, but I have yet to find a solution.
A very simple fopen gives me a
I'm not at all sure about whether this is the problem or not, but I know in the past I've had problems with opening URLs with fopen, often due to php.ini's allow_url_fopen or other unknown security settings
You may want to try cURL in PHP, which often works for me, you'll find an example really easily by googling that.