acrobat reader help essential not working

[hacker]

I installed the 0.4 version of acroread 7 from debian-marillot.  I'm
using ubuntu debian KDE.  It seems odd, but the "Help Essential"
sidebar is blank when I open it.  The Help manual works (by opening in
a separate acrobat window).  It's just the Help => Essential that
opens in a side pane that's blank.

I also have a debian unstable on another disk partition, and it worked
successfully there.  Any idea what needs to be done in ubuntu to get
this working?