Hello Michael, Bruce,
I'm trying to read SMART data off of SATA drives connected to a SAS HBA (via a SAS expander).
It does not return the all SMART data (as shown below).  I know these SATA drives support SMART because I was able to read the data via a different setup/method.

smartctl version 5.33 [i586-mandriva-linux-gnu] Copyright (C) 2002-4 Bruce Allen
Home page is http://smartmontools.sourceforge.net/
Device: ATA      HITACHI HDS72505 Version: A22A
Serial number: ZAG4LARD
Device type: disk
Local Time is: Fri Feb 17 12:05:31 2006 PST
Device supports SMART and is Enabled
Temperature Warning Disabled or Not Supported
SMART Health Status: OK
Error Counter logging not supported
Error Events logging not supported
Device does not support Self Test logging

For SAS drives, it will return all SMART data.  Is there something I missed?  Does 'smartctl' use some passthru mechanism in the driver to send SATA commands to SATA drives? BTW, I'm running linux kernel 2.6.
Thanks very much for your help.
Best regards,
Quat Le