Thumbnail name vs Adblock Plus filter

Hi,

I’m here because I have to modify a file at each update of WordPress. I made a killer template that takes care of 99% of the posting process, which is great because I post a lot (http://www.thecycler.net).

The problem is that my pictures are 300×250 and I use Adblock Plus plugin in Firefox, which has a default filter for filtering any image containing 300×250 in its name (stupid I know)… took me a while to figure that out.

I modified media.php in wp-includes and changed the {width}x{height} to w{width}h{height} format.

Is there any filter that would allow me to do the same thing and remove the chore of modifying that file at every update of WordPress?

kthxbye