Query multiple custom taxonomy terms?

I created a custom taxonomy named ‘technologies’ but cannot query multiple terms like I can with categories or tags.

These querys DO work:
query_posts('tag=goldfish,airplanes');
query_posts('technologies=php');

However, neither of the following work correctly:
query_posts('technologies=php,sql');
query_posts('technologies=php&technologies=sql');

My objective: Show all posts with a technology of ‘php’ and all posts with a technology of ‘sql’

Any ideas? Is this even possible? Thanks!