Extend the replace modes with span tag

Beeing very annoyed about the tooltip behaviour of firefox I searched for a solution without the Firefox add-in called "Long Titles", because probably only a few people of my audience (if any at all) will know about it.

Well, I found a CSS based solution which avoids the firefox 'title' problem.
I've done it only for the 'acronym link' because that was enogh for me but I think it might be worth to be a general option for glossary:
Please add an option to use either the title attribute or the span tag to include the text of glossary entry.

Here is what I've done:
I've changed the glossary.css

extended:
a.glossary-term
with: position: relative;

new:
a.glossary-term span
a.glossary-term:hover span

a.glossary-term {  position: relative;
  text-decoration: none;
  border-bottom: 1px dotted #080;
  color: #080;
  cursor: help;
}

a.glossary-term span {
    display: none;
}

a.glossary-term:hover span {
    position: absolute;
    top: 1px;
    left: 75px;
    width: 400px;
    display: block;
    text-decoration: none;
    color: black;
    background: #FDFFCF;
    border: 1px solid black;
}

I've also changed a bit of the glossary.module file:

In the function _glossary_filter_process($format, $text) I've replaced the handling of the case 'acronym link' with the following code:

   case 'acronym link':
       $ins_before = '<a class="glossary-term" href="'. url($linkto, null, null, $absolute_link) .'">';
       $ins_before .= '<span>'. check_plain($term_title) .'</span>';
       $ins_after = '</a>';
        break;

It works like a charm with Firefox and IE7.
An example is available at http://www.mobdata.de/Produkte/Handgeraete_fuer_die_mobile_Datenerfassung
Look for Schutzklasse and hover over it.