When pluralizing <acronym>FOO</acronym>, we used to have both
of the following styles:

<acronym>FOO</acronym>s
<acronym>FOOs</acronym>

The first one keeps only the *real* acronym letters inside the
element, so pick this one (somewhat arbitrarily) and fix the rest.

Submitted by: ganbold(at)micom.mng.net (partially)