Are you taking it from the 'Grab the HTML/BBCode' pop-up? If so, then it might have the wrong one selected (of the two buttons at the foot of the pop-up). Here's what I get from each in turn:
<a href="http://www.flickr.com/photos/luckypoet/6379339997/" title="Birds of prey aplenty by Lucky Poet, on Flickr"><img src="http://farm7.staticflickr.com/6031/6379339997_6ca7818117_z.jpg" width="640" height="425" alt="Birds of prey aplenty"></a>
Birds of prey aplenty by
Lucky Poet, on Flickr
If it's not that, then I'm stumped...