OT: xemacs: folding elements

Hi,

I use Xemacs and psgml(xml)-mode for writing my XML. What I'd like to know 
is if anyone of you knows of a way to hide <indexterm>s inside paragraphs. 
I use sgml-fold-* and sgml-unfold-* quite a lot for lists of any kind. But 
these commands don't work with all elements especially not with 
<indexterm>. 

In my opinion the <indexterm>s markup makes reading the source somewhat 
difficult. Since it is so easy to fold a list (C-c C-f C-e) I wonder if 
there's something similar for <indexterm>s. I googled around but couldn't 
find anything. 

Thanks in advance ...

Thomas Gier
Technical Writer