try Qhull without
special processing for narrow distributions.
For example, special processing is needed for:
<pre>
         rbox 1000 L100000 s G1e-16 t1002074964 | qhull Tv Q10
</pre>

<p>You may turn off the warning message by reducing
qh_WARNnarrow in <tt>user.h</tt> or by setting option
'<a href="qh-optp.htm#Pp">Pp</a>'. </p>

<p>Similar problems occur for distributions with a large flat facet surrounded
with many small facet at a sharp angle to the large facet.
Qhull 3.1 fixes most of these problems, 