Jams

My colleague is back from China. He was at Kunming airport, waiting for a flight to Hong Kong when he felt a tremor beneath his seat and it dawned on him that the building may be on the verge of collapse. A few moments later he felt it again and the chandelier in the waiting room (only the Chinese could have chandeliers at airports) swung alarmingly. He texted his wife, "I think I may be in an earthquake!" A few seconds later she replied, "Yes, I've just seen it on the BBC news." He was hundreds of miles away from the epicentre, had no idea of the scale of it and caught his flight. A couple of hours later all the flights were cancelled so he was lucky not to have been stuck there.
Talking of jams, I cut down all my remaining rhubarb and have made 5lb of rhubarb and ginger jam. I added pectin but it still hasn't set. Are there any jam experts out there who know whether reboiling with more pectin will work?