The most common source of that problem, according to few searches on google seem to point to using absolute positioning. This was not an explanation that I found too satisfying, first because I was not about to change my layout, and second because most of the references were at least 3 years old.
So I kept digging, and came accross an other solution from Tom Muck in Fix for IE selection bug. Unfortunately, this did not apply for me.
And finally, I found the most conspicuous post on the drupal site where if you don’t use the form
<link .../>
instead of
<link ...></link>
this will be enough to break internet explorer. Who would have thought! Well, maybe by now I should now better.
And the worst part of that? Well it was the second time in 2 months I needed that, and for the life of me, I could not remember what I had done the first time around. So unless this server crashes too, I’ll know where to find the solution next time.