As far as I know, they aren't. I might be wrong, Sven can confirm.
Digital signatures aren't a guarantee of security. Several years ago, a criminal stole a digital signature and used it to sign a malicious program containing a virus that used the same name than my game to confuse end users.
You can build JogAmp by yourself and sign it, you don't need us to provide libraries with signed signatures. Don't forget that code signing certificates aren't free of charge.
Maybe -fstack-protector-strong would do the job with gcc but again, Sven knows better than me. The last time I had to compile the C code of JOGL under Windows, I used gcc, Visual Studio isn't supported out of the box and it's ok for me, it's not necessary, supporting it would cause some problems.