FYI, all I did with my plugin is I packaged most of that Ruby installation in the above post with my plugin. I tried to trim most of the fat as there are source files etc. in there. Probably still left a huge amount in that doesn't need to be...
Edit: I know I've made several post about this before, but I tried to do the same thing on Mac and I could never get a 1.8.5 that would work (I even tried compiling it but every version I could find after scouring the internet was missing the thread.so standard C extension. A sad story... we still don't have Mac support because of this >.< ).
So anyway if you want to reproduce the error, just drop that installation into your \Plugins\Foo folder and try requiring openssl.so on Vista. As always you may want to adjust your $LOAD_PATH variable.