Anaconda sometimes fails SL linux 55

I have a problems that sometimes occur. It sometimes occur more often 
when I trying to kickstart more nodes. Sometimes it happens only to one 
node several times. Often it helps to just reboot and start again. 
Sometimes not. This is the error message I get.

Running anaconda, the Scientific Linux system installer - please wait...
Traceback (most recent call last):
   File "/usr/bin/anaconda", line 604, in ?
     instClass = getInstClass(opts)
   File "/usr/bin/anaconda", line 358, in getInstClass
     from kickstart import Kickstart
   File "/usr/lib/anaconda/kickstart.py", line 17, in ?
     from installclass import BaseInstallClass, availableClasses, 
getBaseInstallClass
   File "/usr/lib/anaconda/installclass.py", line 581, in ?
     baseclass = getBaseInstallClass()
   File "/usr/lib/anaconda/installclass.py", line 566, in 
getBaseInstallClass
     allavail = availableClasses(showHidden = 1)
   File "/usr/lib/anaconda/installclass.py", line 519, in availableClasses
     exec(cmd)
   File "<string>", line 1, in ?
   File "/usr/lib/anaconda/installclasses/rhel.py", line 18, in ?
     class InstallClass(BaseInstallClass):
   File "/usr/lib/anaconda/installclasses/rhel.py", line 28, in InstallClass
     repos = { "Scientific Linux Security Updates": 
("ftp://ftp.scientificlinux.org/linux/scientific/5rolling/%s/updates/security" 
%(rpmUtils.arch.getBaseArch() ,), None) }
NameError: name 'rpmUtils' is not defined
install exited abnormally [1/1]
sending termination signals...done


Any hints?

-- 
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Jonas Hagberg        [email protected]
Systemexpert           Projektledare UPPNEX
UPPMAX                  tel  018 - 471 1026
                         fax: 018 - 51 19 25
Uppsala universitet
Box 337, Lägerhyddsv 2E, Hus 4, room 4111
751 05 Uppsala             www.uppmax.uu.se
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