Because 1 page is barely enough for all users (does anyone still use 640Ko of memory?), and because it can be difficult for users to set how many pages they need after pressing the "print" button (what with the print dialog being over the diagram etc), we decided to go the opposite direction: pages are set directly in the diagram (and can be different for each diagram).
Look in the "Symbol" view while you clicked on a diagram's background, and you'll see the bottom two options are "Show Page boundaries" and "Page size", which allows you to indeed see the boundaries of the pages that will be printed, and set the size of said pages - default size being A4V, standing for A4 (297 x 210mm) Vertical (portrait).
More precisely, you can use the following formats:
- A0V, A1V, A2V, A3V, A4V A5V for respectively A0 (1189 x 841mm), A1 (841 x 594mm), A2 (594 x 420mm), A3 (420 x 297mm), A4 (297 x 210mm), A5 (210 x 148mm) format in vertical orientation ("portrait").
- A0H, A1H, A2H, A3H, A4H A5H for the same formats but in horizontal orientation ("landscape").
- any value of the following format: WxH where W is the width in millimeters and H is the height in millimeters (and decimal is indicated by a point '.' and not a coma ',')
- any value of the following format: W"xH" where W is the width in inches and H is the height in inches (and decimal is indicated by a point '.' and not a coma ',')
Of course you can mix inches and millimeters (like W"xH) but I wouldn't advise you to do so.