Cartblock Ajax mode not working on virtual URL

[gregs_legs]

Hi,

I recently did a clean install of 1.4.7.3 so that I could use a theme that I particularly liked. I then updated to 1.5.4.1 using one click update. Everything works fine except:

 

When I 'locate' my shop at a virtual URL the ajax cart has a problem. When I try to add something to a cart I get:

 

Impossible to add the product to the cart.

textStatus: 'parsererror'

errorThrown: 'SyntaxError: JSON.parse: unexpected character' ....

 

It works fine when the shop is located at the physical URL. Also, if I switch off Ajax, the product is added to the cart but I would like my customer to continue shopping so I'd really like the Ajax functionality.

 

I'm new to this stuff and I'm a bit stuck as to what to do next. Any thoughts ?

Cheers