[Crash-utility] Why won't crash read 2.6.19.2 live system?

I am stuck with trying to read access 2.6.19.2 when crash 4.0-3.17 starts. With debug turned on, I get: ... WARNING: cannot read linux_banner string /proc/version: Linux version 2.6.19.2MM2 (mmilgram@scipo) (gcc version 3.4.5 20051201 (Red Hat 3.4.5-2)) #1 SMP Tue Jan 16 10:58:09 EST 2007 linux_banner: crash: kern/vmlinux and /dev/mem do not match! Usage: crash [-h [opt]][-v][-s][-i file][-d num] [-S] [mapfile] [namelist] [dumpfile] Enter "crash -h" for details. If I use the same copy of vmlinux and /dev/mem with gdb, I can read linux_banner: (gdb) p linux_banner $5 = "Linux version 2.6.19.2MM2 (mmilgram@scipo) (gcc version 3.4.5 20051201 (Red Hat 3.4.5-2)) #1 SMP Tue Jan 16 10:58:09 EST 2007\n" I ran crash in gdb and found that read_dev_mem reads 1500 bytes of data from /dev/mem, but all the bytes are 0. Am I doing something wrong? Thanks in advance, Marc