Will a Tamron lens cause sporadic power loss on Canon 300D?

I have used a Canon Rebel 300D and a Tamron 28-300 lens together for 3 years. About 5 months ago, I began having a loss of power at times, low battery reading when battery is full and twice have had my camera freeze up and will not focus. I usually can shut camera off then back on and have power. I have sent camera twice to Canon in 6 weeks - they have replace a couple of electronic items - problem is still occuring. I talked with Canon tech and he says it probably is the use of a Tamron lens on the Canon camera messing up the electroinics of the camera.
What do you think?

The problem was in my Tamron lens. I emailed Tamron describing the problem - they responded quickly saying that I needed to send it in to them to evaluate. I sent it off to Tamron and they fixed it at no charge to me. They updated the electronic power unit. Apparently my lens was from a time before they had lens specifically for digital cameras. I am not sure why it worked without problems for 3 years but all is well now and they assured me that I will not have any more problems. Time will tell.