Hi Paul!

It looks pretty silly when the mousepointer is on a picture and the "tooltip" says "[image]"

OK, as already said that's a bug in M$-IE (pre 7).

• IE 6.0.2900.5512
  
• Seamonkey 1.1.17

If you want to replace the alt-attribute with an empty one, edit functions.inc.php – in the current version 2.1.1 lines 455 and 460. If you have an older version locate the 2nd occurancy of the string

// [img]image[/img]

and edit lines just below. Change from

    if(!isset ($attributes['default'])) return '<img src="'.htmlspecialchars($content).'"
alt="[image]" />';
    return '<img src="'.htmlspecialchars($content).'" style="float:'.htmlspecialchars(
$attributes['default']).';padding:'.$padding.';" alt="[image]" />';

to

    if(!isset ($attributes['default'])) return '<img src="'.htmlspecialchars($content).'"
alt="" />';
    return '<img src="'.htmlspecialchars($content).'" style="float:'.htmlspecialchars(
$attributes['default']).';padding:'.$padding.';" alt="" />';

The better solution (which works in all browsers, and gives in text-browser still the information that an image is there) would be to keep the alt-attribute and add an empty title-attribute (for IE<7 only):

    if(!isset ($attributes['default'])) return '<img src="'.htmlspecialchars($content).'"
alt="[image]" title="" />';
    return '<img src="'.htmlspecialchars($content).'" style="float:'.htmlspecialchars(
$attributes['default']).';padding:'.$padding.';" alt="[image]" title="" />';

Untested! I'm not using v2 myself (but I'm using a similar solution in my installation; check this post in IE6).