Multiple Upload Image Problem - Resize GIF files

The Multiple Image Upload script seems to handle .jpg images without problems.
However, .gif files return the error:

"Error converting image (image resize). Image processing library not available or does not support operation. (imagemagick library is not working or not found)."

The problem is caused by the fact that script that I'm using tries to pass a parameter that is not valid for gif processing:

myimage.gif' '-quality' '80'

The "quality" parameter works only for jpeg and .png files as described here:

http://www.imagemagick.org/script/command-line-options.php#quality

Please ensure that the script makes difference between .gif and .jpeg files and use the correct parameters so we can resize the images properly.

Thanks in advance,
Márcio