Unclear license situation in ruby1.8 (GPL, SSL, Ruby license)

[Lucas Nussbaum <lucas@lucas-nussbaum.net>]

Hi,

We (Ruby maintainers) are a bit confused by the situation of the ruby1.8
package. We think we are fine (the package has been in Debian for years,
has probably been reviewed by ftpmasters many times), but we are not
sure anymore why we are fine ;)

The situation is the following.

Ruby is licensed under the Ruby license, or GPLv2. The exact terms for
the choice are:
Ruby is copyrighted free software by Yukihiro Matsumoto
<matz@netlab.jp>.  You can redistribute it and/or modify it under either
the terms of the GPL version 2 (see the file GPL), or the conditions
below:
[ Ruby license ]

The Ruby license doesn't appear to be based on any other license.
gnu.org says:
  License of Ruby
  This is a free software license, compatible with the GPL via an
  explicit dual-licensing clause.
I don't know if the Ruby license is free itself, or free because of the
dual-licensing clause (so it would only be free under GPLv2).

When building ruby, two interesting extensions (separate .so files) are
built.
- readline.so is built by linking with libreadline5 (GPLv2)
- openssl.so is built by linking with openssl.

readline.so is not linked with openssl, openssl.so is not linked with
readline.

Questions:
1/ Can we ship those files?
2/ Can we ship those files in the same binary package?
3/ Can we distribute a ruby application that "require" (that's the ruby
keyword for loading libraries) both readline and openssl?

Thanks,
-- 
| Lucas Nussbaum
| lucas@lucas-nussbaum.net   http://www.lucas-nussbaum.net/ |
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