I borrowed your wording to write again to one.com support...
In that case if you indeed do not support openssl on your servers then you non of your clients won't be able to use PayPal on their website, with any ecommerce solution as PayPal requires that the IPN communication with them is done in SSL for security reasons. i have many sites with you and many of my clients are now asking to have shopping carts with PayPal. It will be unfortunate but that means I'll have to move them elsewhere.
...and I got this response:
I apologize but it seems the supporter was mistaken on the matter at hand. We don't support https, but we do support openssl on outgoing connections... it is supported you just need to add the code from paypal and make sure you setup the proper API and keys needed for it. This is all done on your Joomla panel and plugin you are using.
So now I've wasted a few more days, I'll try again to see if I can get the cart connecting to PayPal properly.