[Orgmode] performance problems with drawers

[Al]

Hello,

I'm trying to use emacs org-mode to keep my bookmarks (using the
org-annotation-helper.el method). I find this really great, except performance
issues.

My .org file contains ~5000 entries, organized in a tree like this:

#+DRAWERS: MYDATA

** net
*** www
**** [[http://www.w3.org/][W3C - The World Wide Web Consortium]]
:MYDATA: 
  :Entered:   [2000-03-06 10:29:04]
  :LastVisit: [2000-08-31 16:32:15]
:END:

Some optional text

**** [[http://www.xml.com/pub][XML.com - XTech 2000 Conference]]
:AEDATA: 
  :Entered:   [2000-03-06 10:29:49]
  :LastVisit: [2001-10-08 15:37:09]
:END:

The problem is that with the drawers activated, it's *very* slow. Cycling the
visibility mode takes more than 10 seconds.
If I remove the drawers configuration line (#+DRAWERS: MYDATA), speed comes back
to reasonable levels, but obviously I lose the drawer effect.

Is there a solution to improve the speed and using the drawers ?

Thanks in advance.