The Tumblr blogging service halts posting for a short period to allow its engineers to clean up a fast-spreading JavaScript virus.

A proof-of-concept multiplatform macro worm that can attack OpenOffice on Windows, Mac and Linux PCs, has been sent to security vendor Sophos.

Anti-virus experts are giving a collective thumbs-down to a proof-of-concept virus targeting OpenOffice and StarOffice, dismissing the creation as a silly publicity stunt.