Canon Offers a Locking Mode Dial Mod For the EOS 5D Mark II and 7D dSLRs
The folks at Canon are aware of the problem and are offering a fix. Canon will modify your EOS 5D Mark II or EOS 7D mode dial with a handy lock. This will keep your dial in place unless you push the central button that releases the lock.
You'll be able to have your camera modded starting on December 6. Pricing is $100 per mod currently, but Canon says that this price could change in the future.
For more information about either of these Canon EOS cameras, Click on the names above to see our full, in-depth reviews. 