Did generic extension tubes destroy my camera?

My 5D exhibited a peculiar lockup three weeks back during a shoot, which I was able to clear after powering off, removing the battery and lense, and continue the shoot.

Last week I purchased a set of generic extension tubes and tried them on my 10D and they worked with no problem. Then I put one on my 5D and it died after a few seconds (after a power off, card insert, power on, card format, death). This was the first time I had used the camera since the lockup incident.

I'm sending it in to get repaired but I'm nervous about using the tubes when it gets back. Is it just a coincidence or has anyone heard of tubes shorting out a camera?

Here's the generic tube set: http://www.adorama.com/MCAETEOS.html

Thanks,

Wayne

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[Insert incredibly profound statement here.]

http://www.wsolumphoto.com