[XeTeX] unexpected improvement with XeLaTeX

[Pablo Rodríguez]

Hi there,

due to a bug with hyperxmp and xelatex (that I'll report later), I have
accidentally discovered that the xdvipdfmx version included in TL2009
(and maybe in TL2008) provides much better compression rates using the
-V 5 option.

How can I set that all xelatex generated files use PDF 1.5 as their
minor PDF version?

Thanks for your help,


Pablo