Other Help Topics :: USB install HOWTO
Well, I took some tips from this thread (http://damnsmalllinux.org/cgi-bin/forums/ikonboard.cgi?act=ST;f=5;t=177;st=30) and decided to edit my linuxrc file so that it would try to mount /dev/sda on bootup, and not just /dev/sda_. I just booted into Knoppix off of the CD, mounted my USB stick, unpacked miniroot.gz, mounted miniroot and then added /dev/sda to the linuxrc file. Then I zipped it back up and it worked just fine. BTW, I was using the July 12th bootusb.img.
Perhaps whoever manages the bootusb.img will want to add /dev/sda to the linuxrc file of bootusb.img permanently.
original here.