Regarding Oc'ingOk , loaded it up and it reads the CF Card info
Printed this on the screen

Some useful info at least , this is a Lexar 1066x 32GB
I see the card runs as a PCMCIA & the UDMA in Advance i/o --0x0003 , UDMA6 ? More then likely from the dm-spy logs
This image (upper) is really odd. Look at this image (lower - older cf_acc version) from the 40D.

There are more questions than answers ..
Why are features supported the excat same ? 40D (digic 3) only runs in slow PIO mode, while digic 4 run lighting fast UDMA mode. The digic 4 code says UDMA , and the digic 3 code only says PIO mode.
This is really fishy ..
1. Features supported are the exact same (no can't be !).
2. No mention to UDMA support or enabled in upper image, but digic 4 runs UDMA
3. No mention to PIO mode 5,6 support in lower image, but digic 3 runs 80 ns cycle (pio mode 6)
4. Both upper and lower image, says support PIO 3+4 only.
5. lots of others words are exactly the same.
The Features Enable words are different, but the CFA3.0 or CFA4.0 specifications does not mention anything about these bits, they are reserved. Im talking about word 86. Sorry can't show the specs, they are "copyrighted". so need to use google yourself.
Seems like the CF card controller is a part of the DIGIC-SOC chip itself, and the cf card controllers "words" are just dummy data. Or am I missing something ? it not then this basically means that OC'ing can only be done with CFDMA I/O (0xC0620000 for digic 4)