Poster printing on four A4 sheets in Linux

I wanted to print a poster sized image but I only have an A4 printer. Solution: PDFPoster, as described on the the Propheris blog. The application is in the Debian repository. The Ubuntu manpage helped me find the right command for a four A4 sheet poster:

pdfposter -mA4 -p2x2a4 in.pdf out.pdf