pre-uninstall script in bdist_wininst

[Nils]

Hi.
I am using a postinstall-script like this:
setup(
    ...
    scripts=['scripts\install.py'],
    options = {
        ...
        "bdist_wininst" : {
            "install_script" : "install.py",
            ...
        },
    }
)

According to the docs in [1] this script is
a) called after install (with the "-install" parameter) - this works
fine for me...
b) called before uninstall (with tho "-remove" parameter) - this
however does not work.

Can someone please point me to the direction on how to get a pre-
uninstall script working?

btw: With that I am trying to register a com-server on install and de-
register on uninstall - so if other ideas are around I'd love to hear
them, too...

Nils