diff -up sos-2.2/sos/plugins/devicemapper.py.orig sos-2.2/sos/plugins/devicemapper.py
--- sos-2.2/sos/plugins/devicemapper.py.orig	2011-02-25 12:02:20.000000000 +0000
+++ sos-2.2/sos/plugins/devicemapper.py	2011-02-25 12:02:38.000000000 +0000
@@ -32,6 +32,7 @@ class devicemapper(sos.plugintools.Plugi
         self.collectExtOutput("/sbin/dmsetup info -c")
         self.collectExtOutput("/sbin/dmsetup table")
         self.collectExtOutput("/sbin/dmsetup status")
+        self.collectExtOutput("/sbin/dmsetup ls --tree")
 
         self.collectExtOutput("/usr/sbin/vgdisplay -vv", root_symlink = "vgdisplay")
         self.collectExtOutput("/usr/sbin/vgscan -vvv")