#commedialogo
{
   margin-left:200px;
   outline:none;
   display:block;
   width:120px;
   height:24px;
   background:#54644E url('../images/our_logo.gif') no-repeat;   
}

#commedialogo:hover 
{
   background:#54644E url('../images/we_made_this.gif') no-repeat; 
}