iostat not working properly with -x on SLES9

Hello, I'm testing iostat on a SLES9 with kernel 2.6.5 (default) and 2.6.8.1 (vanilla). This is the command line and result: linux:~ # iostat -t -d -x /dev/cciss/c0d0p2 5 Linux 2.6.5-7.97-default (linux) 10/01/04 Time: 10:58:27 Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util Time: 10:58:32 Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util As you can see the metrics are not showed even if I can query them from proc: linux:~ # cat /proc/diskstats|grep cciss/c0d0p2 104 2 cciss/c0d0p2 10186 351860 8478 67824 Any idea? Thanks Fabrizio