ICRC error?

[Michael Sig Birkmose]

Hi!
I just installed a new disc in FreeBSD 4.8, and updated my fstab with the
following extra info
/dev/ad2s1b             none            swap    sw              0       0
/dev/ad2s1e             /mnt/space      ufs     rw              2       2

During the boot i get the following:

ad0: 58644MB <IC35L060AVVA07-0> [119150/16/63] at ata0-master UDMA100
ad2: 38166MB <ST340016A> [77545/16/63] at ata1-master UDMA100
Mounting root from ufs:/dev/ad0s1a
ad2s1e: UDMA ICRC error reading fsbn 2097247 of 16-31 (ad2s1 bn 2097247; cn
130 tn 139 sn 40) retrying
ad2s1e: UDMA ICRC error reading fsbn 2097247 of 16-31 (ad2s1 bn 2097247; cn
130 tn 139 sn 40) retrying
ad2s1e: UDMA ICRC error reading fsbn 2097247 of 16-31 (ad2s1 bn 2097247; cn
130 tn 139 sn 40) retrying
ad2s1e: UDMA ICRC error reading fsbn 2097247 of 16-31 (ad2s1 bn 2097247; cn
130 tn 139 sn 40) falling back to PIO mode


Now what does this mean?
I also wonder why it says that it found ad2 as UDMA100 since it is actually
an UDMA33 disk?

Best regards,
Michael