[systemd] Failed to set capabilities on file

[ruidc]

On my sheevaplug, I have systemd installed (but have not switched to it yet) and upon running upgrade today got:

$this->bbcode_second_pass_code('', '
(6/6) upgrading systemd [######################] 100%
Failed to set capabilities on file `usr/bin/systemd-detect-virt' (Operation not supported)
usage: setcap [-q] [-v] (-r|-|<caps>) <filename> [ ... (-r|-|<capsN>) <filenameN> ]

Note <filename> must be a regular (non-symlink) file.
')

any ideas what's gone wrong and how I can fix it?