By Dinesh Nair DUBAI (Reuters) – Qatar Holding LLC is among a handful of investors that have put money into BlackBerrys $1 billion convertible debt offering, a source familiar with the financing plan said on Wednesday. The Qatari sovereign wealth fund bought as much as $200 million of the offering, in which Fairfax Financial Holdings Ltd, BlackBerry Ltds largest shareholder, has itself put in $250 million. A spokesman for Qatar Holding declined to comment. Fairfax and BlackBerry declined to identify other investors in the debt offering.