A sony dealer said that these sony batteries may charge on my Canon CA-910 charger (standard XL1s charger).

I asked because I wanted to use sony's excellent top camera light HVL 20DW2 light on my XL1s. I did not want to have to buy another charger though. It's an excellent light, I used to use it in my old PD 150 days and it's very well priced at around £130/ $150.

Anyone tried this?
regards to all
Mark

If both battery types are Li ion 7.2V (two 3.6V cells), simular capacity (Ah) and have the same fixation and polarity, there will be no problem.

I certainly wouldn't risk it. An infolithium battery is a whole different type of battery than a canon battery. Even if it would fit the charger -- and I doubt it would -- you risk explosion and fire.
A desktop charger for the sony battery just shouldn't be very expensive. I had one that came with a mavica camera a few years back. It was a small device. I'd be surprised if it cost more than a typical L series battery.

and can be had at B&H Photo for $45.

Hope this helps.