Convert makes page go out of order?

[itsmattxp]

Recently, I've been trying to fix a problem with my nook concerning the order of the jpg files. When I converted the folder containing all the jpgs to .rar, I made sure that they were in the order that I wanted them to be in. I labeled them as 01,02,03, etc. Afterwards I changed rar to cbr and then to epub through calibre. Regardless of what I do, it seems like the jpgs are always in the wrong order, for instance page 40 will come before page 3. Is there anyway to fix this? Any help would be appreciated, thanks!