Description of problem:

Entering debug mode on a ppc64 system accessed by serial console fails.

Version-Release number of selected component (if applicable):

 * anaconda-12.7

How reproducible:


Steps to Reproduce:
1. Boot installer and transition to stage#2 graphical or vnc
2. Trigger a traceback (accidental of forced with updates=http://jlaska.fedorapeople.org/traceback.img)
3. At traceback dialog, hit "Debug"
  
Actual results:

Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/meh/handler.py", line 156, in <lambda>
    sys.excepthook = lambda ty, value, tb: self.handleException((ty, value, tb), obj)
  File "/usr/lib/python2.6/site-packages/meh/handler.py", line 113, in handleException
    responseHash[rc]((ty, value, tb))
  File "/usr/lib/anaconda/exception.py", line 52, in runDebug
    isys.vtActivate(1)
  File "/usr/lib/anaconda/isys.py", line 484, in vtActivate
    _isys.vtActivate (num)
SystemError: (22, 'Invalid argument')

Expected results:

Debug shell on tty1
Additional info: