PATCH current.html: mutt and qdbm

It looks OK in lynx.

Index: current.html
===================================================================
RCS file: /cvs/www/faq/current.html,v
retrieving revision 1.415
diff -u -p -r1.415 current.html
--- current.html	16 Aug 2013 11:23:44 -0000	1.415
+++ current.html	17 Aug 2013 02:02:27 -0000
@@ -702,6 +702,8 @@ After updating, restore them as follows:
     # To convert a batch:
     for i in *.xml; do rrdtool restore $i ${i%.xml}.rrd; done
 </pre>
+<li>If using mutt with qdbm as cache, remove the database files and run mutt.
+It will regenerate the cache. Otherwise mutt will crash.
 </ul>
 
 <p>