Xen users - Jan 2014 - XenProject Q&A: /etc/init.d/xcp-xapi doesn't start: 'Error: Connection refused (calling connect )'

On the XenProject.org Q&A section, user "Mark" asks the following:

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Topic: /etc/init.d/xcp-xapi doesn't start: 'Error: Connection refused
(calling connect )'

I'm stumped by the above.
Fresh install of debian wheezy. install params:
netcfg/disable_autoconfig=true
cdrom-detect/eject=false
base-installer/install-recommends=false

Followed
http://wiki.xenproject.org/wiki/XAPI_toolstack_on_a_Debian-based_distribution.

/etc/xcp$ cat inventory
CURRENT_INTERFACES='xenbr0'
BUILD_NUMBER='0'
CONTROL_DOMAIN_UUID='226e9869-72bc-4680-bf98-686dbfcc9bbe'
INSTALLATION_UUID='226e9869-72bc-4680-bf98-686dbfcc9bbe'
MANAGEMENT_INTERFACE='xenbr0'
PRIMARY_DISK='/dev/sda1'
PRODUCT_VERSION='6.0.0'

Then xcp-xapi returned FATAL: Module blktap not found. I installed the
linux-headers for the kernel and rebuilt dkms. Now I get the above
error and in the xcp-xapi.log:

Caught exception at toplevel:
'Db_exn.Uniqueness_constraint_violation("VM", "uuid",
"226e9869-72bc-4680-bf98-686dbfcc9bbe")'

which I can't find anything on. The log file for more info is here
http://phosph.re/s2c/xcp-xapi.txt. XAPI will not start right now, and
I cannot play with xen as a result.

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If anyone has insight for Mark, please email me so I can forward it to
the Q&A entry (or you can enter it yourself, if you feel so inclined,
at
http://xenproject.org/help/questions-and-answers/etc-init-d-xcp-xapi-doesn-t-start-error-connection-refused-calling-connect.html

Thanks,

Russ