im predicting that even though that it looks like nintendo has the rights to all the original SMRPG characters, they don't. i say this because i was leafing through the latest issue of nintendo power at the store, and it talked about paper mario. none, i repeat NONE of the characters I read about were in SMRPG (exept mario, the princess and bowser). there are many simalarities, like the Star Rod, and the place called Star Haven, but nothing that was exactly the same. i don't recall seeing any of the characters from the first SMRPG. this may be because nintendo wanted a different storyline, but...well, maybe not.
the issue also told the basic storyline, but, unless you REALLY want me to, i wont spoil it for anyone.
~Formally daFunkster