exchange off line defrag error -1018 (JET_errReadVerifyFailure, Checksum error on a database page)

Hi All
We have a SBS2003 with exchage 2003 SP1 we comeup to the 18gig limit and would like to install SP2
But after a onlime backup & copy /backup of the exchage dir to an other disk. we get the following error
each time we try to run the off LINE DEFRAG :=

CD  exchsrvr\MDBDATA\
E:\exchsrvr\bin\eseutil /d /p priv1.edb /tp:\tempemaildefrag\temppriv.edb
eseutil THEN EXITS WITH :-
 error -1018 (JET_errReadVerifyFailure, Checksum error on a database page)
event logs show:-

event ID=470

eseutil (4572) Database E:\Exchsrvr\MDBDATA\priv1.edb is partially attached. Attachment stage: 4. Error: -1018.

event ID 474;

eseutil (4572) The database page read from the file "E:\Exchsrvr\MDBDATA\priv1.edb" at offset 295747584 (0x0000000011a0c000) for 4096 (0x00001000) bytes failed verification due to a page checksum mismatch.  The expected checksum was 3547725309 (0xd375fdfd) and the actual checksum was 878525284 (0x345d3b64).  The read operation will fail with error -1018 (0xfffffc06).  If this condition persists then please restore the database from a previous backup. This problem is likely due to faulty hardware. Please contact your hardware vendor for further assistance diagnosing the problem.


note - exchange was working but slow

Action taken:-
rebooted the server
read lots of web pages & EE questions !

Any one through ?