[linux-lvm] lvextend docmentation vs. implementation (lvm2-2.02.39), Suse-11.1

[Linda A. Walsh]

I have been trying to use the lvextend command using the documented
size format:  of +[number][%{LV|PV|VG|FREE}] --
specifically
+50%LV.

tried multiple variations on LV -- no luck.  Is this broken or
is this just not working in my setup, or am I doing something
wrong?  It fails with:
Invalid argument +5%LV
Error during parsing of command line.

Advice?
thanks,
-linda