This happened to me, last year--it was an unpleasant surprise, at the time. After flying a segment, I was able to get the ticket reissued in the US as an electronic ticket; however, all of the tax info was separately printed out and handed to me with the warning, "Don't lose this piece of paper with the tax details, especially if you intend on making any changes."
You are lucky ?
CTO of CX TYO simply refused to issue e-ticket.
Last year (March 2007), CX Tokyo City Ticket Office could not issue e-ticket for my 13 segments AONE3.
They said they could not input tax/surcharge info into e-ticket database due to amount of info.
They attached paper of tax/surcharge calculation to back of all ticket coupons(e.g. 13 copies for flight coupons and a few copies for passenger reciepts)
They said they had no idea about ticket issueing when e-ticket is required.