well, the decimal symbol (windows settings) is a comma and not a point ... i don't want to change this setting because of other applications.
BUT: on my laptop i use (exactly like on the pc) the german settings ... and the exported ps-file is ok! therefor i think that there must be another solution (?).
i thought about problems with german windows-settings (country "Österreich") but this doesn't seem to be the problem either. i've replaced all the settings with "the germany-settings" without having success.