Down-level poster gets clipped

I'm testing my banner on IE8 where it shows my Down-Level image, which gets hidden, but scrollable.
My whole image size is 300x250 and now it shows something like 300x132.
Has anyone else encounter this problem? I would be very helpful for the solution.
Preview:

The image code in the edgePreload.js:
dlContent={dom:[{id:'Poster2',type:'image',tag:'img',linkURL:"http://parduotuve.vz.lt/prenumerata/37",linkTarget:"newWindow",rect:['0','0','300px','250px','auto','auto'],fill:["rgba(0,0,0,0) ",'images/Poster.png','0px','0px']}]};

I've tried changing it but that didn't help, or I've had been changing it wrong.