The link that the system is creating now looks like this: Newsrss instead of
News.rss
I found the problem here (CGFeedMaker.module.php, line 273):
	if( !empty($defext))
	  {
	    $url = substr($url,0,strlen($url)-strlen($defext));
	    if( !endswith('.',$url) ) $url .= '.';
	  }  
this line: f( !endswith('.',$url) ) $url .= '.'; is inside o another if
statement. In the last release, the if statement was after if( !empty($defext))
... block. So i moved it like this:

	if( !empty($defext))
	  {
	    $url = substr($url,0,strlen($url)-strlen($defext));
	  }  
  if( !endswith('.',$url) ) $url .= '.';

and now it works.