CSS refers to non-existant header-image.gif

Hi,

./css/main.css says

#header #header-image {
  position: absolute;
  background: url(../images/header-image.gif) no-repeat;
  width: 371px;
  height: 263px;
  right: 10px;
  top: 0;
}

while this header-image.gif is not to be found.

Cheers,
Nico