2.4.18 - iostat problem with DAC960

2.4.18 - iostat problem with DAC960

[Cliff White]

We are running some benchmarks with raw disk connected to a DAC960 
controller. We are having issues with getting proper stats from iostat.

We've tried the latest version we could find ( sysstat version 4.0.6 ) 
In normal use, we get bizzare numbers, like this:
Device:    rrqm/s wrqm/s   r/s   w/s  rsec/s  wsec/s    rkB/s    wkB/s 
avgrq-sz avgqu-sz   await  svctm  %util
/dev/rd/c0d0
             0.00   0.00  0.00  0.00    0.00    0.00     0.00     0.00     
0.00 42933903.02    0.00   0.00 100.00

Looking at /proc/partitions, we are also confused, since we see 0 for wio and 
rio (and we just did a big dd ) :
[root@dev8-004 root]# cat /proc/partitions | grep c0d0
major minor  #blocks   name     rio rmerge   rsect     ruse wio wmerge   wsect 
    wuse running  use      aveq
48     0     107504640 rd/c0d0  0   11734288 105255266 0    0   12286553 
104803536 0     2232980 36066697 37688171

Any suggestions? 
cliffw