ppm install failed: 501 Protocol scheme 'https' is not supported ...

Seems odd to me that https is being called on to download from a http site.
I've not seen this sort of error before with PPM.

UPDATE: Try running 'ppm log' (or just 'log' if you're in the ppm shell) immediately after the error has happened. That will hopefully give a better idea of what's going wrong.

There are, however, other problems with the sisyphusion repo at the moment. The hosts have messed with its accessibility again, so it looks like I'll have to contact them .... again.
I keep getting "403 forbidden" errors - even though all files are readily available via the browser.
Last time this happened they had to "whitelist one of ModSecurity rules", so I guess some dickhead has messed with those rules again.

You can still install Net-SSH2 on your perl-5.8.8 by grabbing http://www.sisyphusion.tk/ppm/x86/Net-SSH2-58.tar.gz.
Place that file in some directory along with the following file named Net-SSH2.ppd:

<?xml version="1.0" encoding="UTF-8" ?>
<SOFTPKG NAME="Net-SSH2" VERSION="0,56,0,0">
    <TITLE>Net-SSH2</TITLE>
    <ABSTRACT>Support for the SSH 2 protocol via libssh2</ABSTRACT>
    <AUTHOR>Rafael Kitover</AUTHOR>
    <PROVIDE NAME="Net::SSH2" VERSION="0.56" /> 
    <IMPLEMENTATION>
        <OS NAME="MSWin32" />
        <ARCHITECTURE NAME="MSWin32-x86-multi-thread-5.8" />
        <CODEBASE HREF="Net-SSH2-58.tar.gz" /> 
    </IMPLEMENTATION>
</SOFTPKG>
[download]

(Beware of line wrapping if you copy'n'paste that code.)

Then 'cd' to that directory and run:

ppm install Net-SSH2.ppd --force
[download]

Then go through the same rigmarole for Net-SFTP-Foreign and Net-SFTP-Foreign-Backend-Net_SSH2 .... yuk !!

Grab http://www.sisyphusion.tk/ppm/x86/Net-SFTP-Foreign-58.tar.gz and http://www.sisyphusion.tk/ppm/x86/Net-SFTP-Foreign-Backend-Net_SSH2-58.tar.gz.

Net-SFTP-Foreign.ppd needs to be:

<?xml version="1.0" encoding="UTF-8" ?>
<SOFTPKG NAME="Net-SFTP-Foreign" VERSION="1,77,0,0">
    <TITLE>Net-SFTP-Foreign</TITLE>
    <ABSTRACT>Secure File Transfer Protocol client</ABSTRACT>
    <AUTHOR>Salvador Fandino Garcia</AUTHOR>
    <PROVIDE NAME="Net::SFTP::Foreign" VERSION="1.77" /> 
    <IMPLEMENTATION>
        <OS NAME="MSWin32" />
        <ARCHITECTURE NAME="MSWin32-x86-multi-thread-5.8" />
        <CODEBASE HREF="Net-SFTP-Foreign-58.tar.gz" /> 
    </IMPLEMENTATION>
</SOFTPKG>
[download]

Net-SFTP-Foreign-Backend-Net_SSH2.ppd needs to be:

<?xml version="1.0" encoding="UTF-8" ?>
<SOFTPKG NAME="Net-SFTP-Foreign-Backend-Net_SSH2" VERSION="0,09,0,0">
    <TITLE>Net-SFTP-Foreign-Backend-Net_SSH2</TITLE>
    <ABSTRACT>Run Net::SFTP::Foreign on top of Net::SSH2</ABSTRACT>
    <AUTHOR>Salvador Fandino Garcia</AUTHOR>
    <PROVIDE NAME="Net::SFTP::Foreign::Backend::Net_SSH2" VERSION="0.0
+9" /> 
    <IMPLEMENTATION>
        <OS NAME="MSWin32" />
        <ARCHITECTURE NAME="MSWin32-x86-multi-thread-5.8" />
        <CODEBASE HREF="Net-SFTP-Foreign-Backend-Net_SSH2-58.tar.gz" /
+> 
    </IMPLEMENTATION>
</SOFTPKG>
[download]

(Again - beware of line wrapping if you copy'n'paste that code.)

I'll report back here once I've verified that accessibility to the sisyphusion repo has been restored. (I'm actually currently able to access it with the PPM that ships with StrawberryPerl, but not the one that ships with ActivePerl-5.8.9 .... strange.)

Cheers,
Rob