fix isArray function (tests pass in Firefox 3 now)
fix isArray function (tests pass in Firefox 3 now)

LinusU/buffer,kawanet/buffer,mafintosh/buffer,beni55/buffer,nolanlawson/buffer,nolanlawson/buffer,LiuDeng/buffer,loon3/buffer,SAGV/buffer,btd/buffer,kawanet/buffer,btd/buffer,LinusU/buffer,feross/buffer,SAGV/buffer,feross/buffer,jessetane/buffer,beni55/buffer,feross/buffer,loon3/buffer,mafintosh/buffer,LiuDeng/buffer