Description of problem:
DVD based upgrade of FC7 (from FC6) fails with crash "String index out of range"
Steps to Reproduce:
1. Just start DVD upgrade. After selecting keyboard etc, anaconda crashes.
Created attachment 156761 [details]
Dump file writen to floopy (lucky I had one) during install.
This is caused by blank lines in /etc/modprobe.conf of which anaconda is
intollerant. Therefore, the workaround is pretty straightforward.
*** This bug has been marked as a duplicate of 241991 ***