Printing Custom sized documents

I am so pleased to have found this forum.

I am having many problems printing custom sized documents using Inkscape .42 (and, for that matter, Ragtime Solo). I would like to create and then print banners, 8.5 x 24 to 40 inches long on continuous, banner paper. I am using Inkscape and an HP Deskjet 5650 printer.

After I create the banner, I attempt to print it selecting the banner settings in the printer set-up box. What I get is a print out of either 11 or 14 inches. The printing then stops as though the job was completed. I can not print media longer than 14 inches long. HP assures me that their printers can print banners of this length (I forget how long they can be but its longer then I need).

Are there any suggestions that might help solve this dilemma?

Your help is GREATLY appreciate. Thank you for your time.

jt