Description of problem:
There is a difference between the output of cmd "subscription-manager facts" and
"subscription-manager facts --list" no matter the system is registered or not.

Version-Release number of selected component (if applicable):
subscription-manager-firstboot-1.0.14-1.el5
subscription-manager-gui-1.0.14-1.el5
subscription-manager-1.0.14-1.el5
python-rhsm-1.0.5-1.el5

How reproducible:
always

Steps to Reproduce:
1.run command below:
#subscription-manager facts

2.run command below:
#subscription-manager facts --list

3.compare the output of above 2 commands

Actual results:
1.after above step 3, find a difference:
the item 'net.interface.sit0.mac_address' is different between the output of step 2 and step 3 as below:
When the system is not registered:
the output of step 2 is:
  net.interface.sit0.mac_address: 00:00:00:00:21:01 
the output of step 3 is: 
  net.interface.sit0.mac_address: 00:00:00:00:31:01

When the system is registered:
the output of step 2 is:
  net.interface.sit0.mac_address: 00:00:00:00:00:00 
the output of step 3 is: 
  net.interface.sit0.mac_address: 00:00:00:00:21:00

Expected results:
no different between the output of step 2 and step 3 no matter the system is registered or not.

Additional info: