This issue was solved with changeset r35846.
Vincent, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.
ext/dl: Added documentation. Patch by Vincent Batts.
[ruby-trunk - Bug #6496]
After checking with Aaron I cleaned up some missing capitalization in the patch, improved some generic descriptive documentation, and replaced "== Example" with just "Example:" since the sections were so short.