Monkeybread Software (http://www.monkeybreadsoftware.de/Freeware/) has released version 5.1 of the application, Combine PDFs. The upgrade adds support for French and Italian, automatic metadata, more metadata values, and user selectable fonts for text overlays.
Combine PDFs is a utility that allows you to merge a PDF and image into one PDF file. You can split a PDF file or create a new PDF file with interleaved pages from two different PDF files. Options are available to apply Quartz Filters, add encryption and
Combine PDFs requires Mac OS X 10.3.9. It costs US$30, but version 5.1 is a free update for registered users of version 5.x.