CentOS - Jun 2007 - CentOS 5 problem with 2xRocketRaid 2220

Hi! I have an supermicro storage server
http://www.supermicro.com/products/chassis/3U/932/SC932T-R760.cfm
with two RocketRaid 2220. my problem is that at install a looong time is
spent on detecting some ataxx in order to end in
ATA[0-15].00 : Failed to set xfermode (err_mask=0x4)
for each channel from 16 it can take some 15-20 s.
the same happens at boot time (which can take some 4-5 min).
Is there a way to avoid this?
Thank you for any help,
Best regards,
Adrian