There were talks that the earlier Diesel models have an alternator with a voltage output of 13.8V, but the later ones then have a voltage of 14.1V
I'm not sure about the petrol models, but the resident know-it-all on LZ says the 'Thor' alternators were set at 14.5V (I don't think so as I see 14.1V at my battery when the engine is running!) so are fine with charging Calcium batteries.
I didn't have an issue with my '01, and a MF31-750 (well, it was a MF31-750 under the bonnet - now a 1000) AND a MF31-1000 in the boot. The MF31-750 lasted just over 4 years.
I think most car batteries these days have some calcium in them as it reduces bubbling and water usage, which is how they are all branded as 'Maintenance Free'. There is a LOT of debate, and contradicting information out on the www about it all. All I can suggest is that you check what voltage you are seeing at the battery terminals when charging, and if it's above 14V, then the battery will be getting a decent charge. Even if you need 14.4V minimum to 'fully' charge a calcium battery - it will be 'close enough' I think to keep the battery going for a few years. It was in my case, anyway.
If you are that worried about it, then you could always fit a battery conditioner to it when it's parked up to give it the extra boost to fully charge.