'return' from block need more restriction

```
[Thank feiyu for reporting this]

(1)code snippet:
a = [ "a", "b", "c" ]
a.each {|x| print x, " -- ";return; }

(2)Run

ruby:It is suppose to be an error.The description info is:unexpected
return (LocalJumpError)

xruby:work correctly,output: a --


```

Original issue reported on code.google.com by `xue.yong...@gmail.com` on 21 Apr 2007 at 6:59
