I recently ran into this, too. Because the Asus-Phison SSD drives incorrectly report that SMART is not supported, smartctl normally aborts without actually trying to enable SMART -- but you can indeed force it to try using the -T permissive option:
# smartctl -s on /dev/sda
smartctl 5.41 2011-06-09 r3365 [i686-linux-3.2.0-23-generic] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net
SMART support is: Unavailable - device lacks SMART capability.
A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options.
# smartctl -T permissive -s on /dev/sda
smartctl 5.41 2011-06-09 r3365 [i686-linux-3.2.0-23-generic] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net
SMART support is: Unavailable - device lacks SMART capability.
=== START OF ENABLE/DISABLE COMMANDS SECTION ===
SMART Enabled.
# smartctl -T permissive -a /dev/sda
smartctl 5.41 2011-06-09 r3365 [i686-linux-3.2.0-23-generic] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net
=== START OF INFORMATION SECTION ===
Device Model: ASUS-PHISON OB SSD
Serial Number: OS6Q85000208432
Firmware Version: TST2.04P
User Capacity: 4,034,838,528 bytes [4.03 GB]
Sector Size: 512 bytes logical/physical
Device is: Not in smartctl database [for details use: -P showall]
ATA Version is: 5
ATA Standard is: Exact ATA specification draft version not indicated
Local Time is: Mon May 20 19:26:06 2013 EDT
SMART support is: Unavailable - device lacks SMART capability.
=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
General SMART Values:
Offline data collection status: (0xff) Offline data collection activity
[...]
(At least this worked with both the 4GB and the 16GB ASUS-PHISON SSD drives found in my Eee PC 900.)
I assume the poster of the Sept 2008 smartmontools-database list message had to use -T permissive to get the output shown there; too bad he didn't mention that fact in the post....