ps2pdf resizes page size to wrong format

[Johannes Wiedersich <johannes@physik.blm.tu-muenchen.de>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hello all,

I have two etch machines with practically very similar configuration.
Due to some mechanism that is rather mysterious to me, if I convert the
very same ps-file the page size is changed on one of the two machines,
while the same command works correctly on the other machine.

ps2pdf a.ps a.pdf

produces a pdf with page size 210x297 mm on machine A and a pdf with the
wrong size of 215.9x279.4 mm on machine B.

The ps file is A4 (210 × 297 mm):

/=== a.ps ====================
%!PS-Adobe-2.0
%%Creator: dvips(k) 5.95a Copyright 2005 Radical Eye Software
%%Title: Blatt02.dvi
%%Pages: 2
%%PageOrder: Ascend
%%BoundingBox: 0 0 595 842
%%DocumentFonts: Helvetica Helvetica-Bold Helvetica-Oblique
%%+ PazoMath-Italic Palatino-Italic PazoMath CMR10 Palatino-Roman CMSY10
%%+ CMEX10
%%DocumentPaperSizes: a4
%%EndComments

<snip>
\=== a.ps ====================

I can't find any hints on page settings in ps2pdf's documentation or how
to force it or how it gets the idea of seemingly arbitrarily changing
the page size.

Thanks,

Johannes
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)

iD8DBQFHIEVtC1NzPRl9qEURAsL4AJ4+JaBFobGZSt63ChCERfCDrQrljgCcCblv
GpuZBQAS0XbuqF3ptWULJAo=
=SgYn
-----END PGP SIGNATURE-----