hi
how can I print a job done in a3 to a4 sheets?

I really have no idea, but I hate to see questions go unanswered

I have, well, zero experience printing from Inkscape. Maybe you need to change some printer settings? When I try to print from Inkscape on my XP machine, I do get an option to print on A4 size paper.

The only thing I can think of, as if it were my problem, is to divide the A3 image into 2 pieces, put each one in an A4 doc, then print them. Since you do intend for it to span 2 pages, I have to assume it CAN be divided into 2 pieces. Perhaps it must be?

Other than that, I'm afraid I don't know. But my reply will "bump" your message back to the top, and maybe someone else will see it (who knows what to do).