Finder crashes with External Drive on Sleep Mode

Question

I purchased my new iMac 21,5" less than a week ago, and I haven't had a problem with it except for one that it's been bugging me a lot.
I have a LaCie 1TB Quadra d2 external drive that I use to store footage (since it's HD, the filesize won't fit in my 500TB internal hard drive), but I noticed that sometimes when LaCie external drive enters in Sleep Mode, the Finder freezes and the only two ways around this, is to force reboot, because the Finder won't answer and won't open again, or unplugging the external drive without ejecting him first, which it's not safe for me to do, because I'm afraid of hurting the device, and the files in it are pretty important.
This happens almost everytime, especially after a long time on sleep mode. I usually leave Final Cut Pro transferring files all night (since it takes a long time) so I kinda need the sleep mode, but when I wake up, Finder and Final Cut Pro won't answer.
I updated to Snow Leopard 10.6.8 on day one. Is there a way to fix this? Is it normal? I read somewhere that some users were having trouble with external drives on Sleep Mode, but I can't seem to find any further information about this problem.
Thanks!

Answer 1

I've got a MacBook Pro 13.3" that's a little over a month old, with a LaCie 1TB LaCie d2 Quadra with USB 3.0, #301542U and I'm suffering the same problems and a few others with it. I've got a partition on it set up as my Time Machine backup drive. I've turned off the Put the hard disk(s) to sleep when possible in the Energy Saver preferences but I'm still having the sleep problem with it. According to the LaCie Manual:
By default, your drive will enter Eco Mode after 30 minutes of inactivity in order to conserve energy. To exit Eco Mode, simply access data on the drive and the disk will automatically restart. You can manage this feature using LaCie Desktop Manager. Click the Eco tab.
The LaCie Desktop Manager (in my case) only takes me to the Energy Saver Preferences in OS X to adjust the time there. Turning off Put the hard disk(s) to sleep when possible doesn't seem to make any difference, the drive still goes to sleep after 30 minutes. However, after 15 minutes the drive seems to wake back up, but then during the next 15 minutes goes comatose (no power light). Sometimes it will go through multiples of these sleep wake cycles without going into a coma, but eventually it does go into a coma. This happens in between hourly Time Machine backups.
After locking up Finder, Disk Utility and Time Machine multiple times trying to access the drive in this state I figured out that I could cycle the power switch to regain use of it (with a Finder warning of course) but this will only lead to file corruption eventually and I shouldn't have to resort to this. I've also dismounted it, expecting it to turn off and instead it goes into an extended spin down cycle (rapidly flashing light) and never turns off (or goes to sleep or what ever it's supposed to do) and once again requires turning the power switch off.
This is just too unpredictible and unrelable for me and as soon as I get the opportunity to do a 7 pass erase I'll be returning to the place of purchase. Based on the reviews of other external hard drives a drive from another company doesn't look to be much better of a prospect so I'm not sure what I'm going to do.