Issues with Manipulating Opacity using jQuery in Opera

Question

I'm using the latest version of Opera (11 alpha), but I ran into this issues with 10 (stable) a while back as well.

I am using the following code to animate opacity:

if($('#detailsLM').length>0){ $('#detailsLM iframe').
   animate({opacity:.5},20,'linear').hover(
   function(){
       $('#detailsLM iframe').animate({opacity:1},600,'linear') 
   },
   function(){ $('#detailsLM iframe').animate({opacity:.5},600,'linear') 
   });
}

However,when executed from a javascript file this doesn't work. There's no error. Just doesnt fire.

When I use the Dragonfly javascript console and run the same code above, it works! Any ideas?

By the way, all other major browsers work like a charm.