Taxonomy index in the node object

Hi,

I'm coding a bloch that will display all the nodes that are linked to the same term of the node that is currently rendered. I'm using this code:

	$mynode = node_load(arg(1));
	$results = taxonomy_select_nodes(array($mynode->taxonomy[1]->tid));

This, however, only works for nodes linked to term 1... I'm wondering why the index of the taxonomy object in that array is the same as its id and not just an incrementing index...

Can anyone tell me if this is by design, and if so, maybe a short explanation why and how do I go about to getting the first element of an array (not necessarily the element with index 1) without removing and adding it again with array_shift and array_unshift?

Best regards,
Sylvain Girard