wheezy backport of FreeCAD is not installable

["Michael C. Toren" <mct@toren.net>]

I was very happy to see there is a version of FreeCAD in wheezy backports!
However, it appears to be uninstallable for me.  After adding:

	deb http://ftp.us.debian.org/debian wheezy-backports main 

to my /etc/apt/sources.list file, and doing:

	sudo apt-get update
	sudo apt-get -t wheezy-backports install freecad

I see:

	The following packages have unmet dependencies:
	 freecad : Depends: python-pivy (>= 0.5.0~v609hg-2) but it is not going to be installed
		   Recommends: python-collada but it is not installable
		   Recommends: python-ply but it is not going to be installed
	E: Unable to correct problems, you have held broken packages.

Looking at http://packages.debian.org/python-pivy, I see the version of
python-pivy is 0.5.0~v609hg-1 in wheezy, and 0.5.0~v609hg-3 in both sid
and jessie.  There does not appear to be any version in wheezy-backports.

Should version 0.5.0~v609hg-3 of python-pivy be added to wheezy-backports?

Is there another workaround I can use for the time being?

Thanks!

-mct