This issue was solved with changeset r33977.
Sylvain, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.
doc/re.rdoc: Document difference between match and =~, options with
Regexp.new and global variables. Patch by Sylvain Daubert.
[Ruby 1.9 - Bug #5709]
I altered the wording on =~ mentioning Range and String because the operator is generic and may be overridden to perform other types of pattern matching.