LaTeX: combines several Slides generated by Latex into one page with six PDF files.

I want to combine several Slides generated by Latex into a page with six PDF files and add borders to each Slides. I don't know how to do this? Someone suggested that I add it to the source file
\ Shortdepdf [pages =-, nup = 2x3, frame = true, offset =. 25in 0] {20111117}, but the compiled file is still not very nice, and some content is out.

The solution is to set the offset and delta parameters
\ Shortdepdf [pages =-, nup = 2x3, frame = true, offset = 0 0, delta = 2em 2em] {20111117 },
OK. For the effect, see the attachment.