ahci(4) doesn't work with Hitachi 3TB drive

[Dieter BSD]

FreeBSD 8.2 amd64
ahci(4) and siis(4) were updated 2011-05-15.
<JMicron JMB363 UDMA133 controller>
<SiI3132 SATA controller>
<Port Multiplier 37261095 1706>

Connected a shiny new Hitachi 3 TB disk to JMB363 (no PM):

ada11 at ahcich1 bus 0 scbus5 target 0 lun 0
ada11: <Hitachi HDS5C3030ALA630 MEAOA580> ATA-8 SATA 3.x device
ada11: 150.000MB/s transfers (SATA 1.x, UDMA6, PIO 8192bytes)
ada11: Command Queueing enabled
ada11: 2861588MB (5860533168 512 byte sectors: 16H 63S/T 16383C)

Should connect at 300 MB/s but says 150.

smartctl is not happy:

/dev/ada11: Unable to detect device type
Smartctl: please specify device type with the -d option.
Use smartctl -h to get a usage summary

Attempt to read disk with dd does not work.

ahcich1: Timeout on slot 0
ahcich1: is 00000000 cs 00000000 ss 00000001 rs 00000001 tfd 50 serr 00000000
ahcich1: Timeout on slot 0
ahcich1: is 00000000 cs 00000000 ss 00000001 rs 00000001 tfd 50 serr 00000000
...

kill -9 dd process, wait for ahci to eventually give up,
unplug disk from JMB363, plug disk into 3132 controller via 3726 PM

(ada11:ahcich1:0:0:0): lost device
(ada11:ahcich1:0:0:0): removing device entry
siisch3: SNTF 0x8000
siisch3: siis_wait_ready() calling DELAY(1000)
ada11 at siisch3 bus 0 scbus3 target 2 lun 0
ada11: <Hitachi HDS5C3030ALA630 MEAOA580> ATA-8 SATA 3.x device
ada11: 300.000MB/s transfers (SATA 2.x, UDMA6, PIO 8192bytes)
ada11: Command Queueing enabled
ada11: 2861588MB (5860533168 512 byte sectors: 16H 63S/T 16383C)

Siis talks to it at 300 MB/s, smartctl works, and dd is reading from it.

Ahci talks to Hitachi 2 TB okay, not sure what is different with 3 TB.