In 1.6.7, String.=~(arg) would compile 'arg' into a Regexp and do the
match.  In 1.8.0 it seems not to.  Is this intended, or a bug?

    data = "test-data"
    pattern = "t.*d"

    printf("%s: %s %s\n", RUBY_VERSION,
           (data =~ pattern).inspect,
           (data =~ Regexp.new(pattern)).inspect)

Produces this:

    1.6.7: 0 0
    1.8.0: nil 0