BrowserUk makes a good point, that reinforces my original advice to find the platform and perl version numbers that allow the script to work, and use that. He and I both use threads, but have very different coding styles( he is admittedly slicker, while my style is very clunky and straight-forward ), and that probably explains why we have different luck with different versions.

You probably should not get stuck in relying on a Perl version to run your script, and should upgrade to the latest Perl version 5.10.0 and get the latest version of threads and threads::shared, then write your script to work with that.

My clunky straight-forward style has very little trouble between version levels, because I use few tricks and take alot of precautions. I would be willing to bet your code uses techniques that pushes the safety limits of perl/threads, and probably can be written in a more clunky manner. :-) But IIRC from your cross-posting, my first fix would be to dump Net::SSH::Expect and go with Net::SSH2 ( which works well with threads).