XFCE not accepting devilspie command

[Andrew Conkling]

I've been using Devil's Pie with XFCE since December of 2003 (don't know
which version that would have been).  I just have it to do a small
handful of things and it's worked great but recently, it doesn't want to
accept just one of my commands.  Here's an excerpt from my devilspie.xml
file where the problem is occuring:

<action name="DevilsPieActionHide">
        <property name="skip_tasklist" value="TRUE"/>
</action>
<action name="DevilsPieActionSetWorkspace">
        <property name="pinned" value="TRUE"/>
</action>

It does indeed skip the tasklist (i.e. not show up on the taskbar), but
it does not (to use XFCE lingo) stick like it should.  Again, this used
to work.

Any clues why this wouldn't work?