Have you seen the pictures? It looks like the explosives were sown into the underwear.
Still, the HE suppository is probably the next step.
The pictures do show the sewn spot for the explosives, but the fact he went to the restroom before he tried to explode himself tells me he probably removed them and placed them in the pouch swen into his underpants. If you think about it, why go to the restroom right before you blow yourself up? If he did have them in his anal cavity, removing them and putting them in the pouch makes perfect sense on two levels.
One, you have to get back to your seat above the fuel tank and you can’t go walking through a plane with a bomb. Two, if you are caught trying to explode the bomb as he was, the authorities will be looking at the wrong way he smuggled it onto the plane. I still think given the Saudi bomber of earlier this year, that this guy had the bomb in his butt when he boarded the plane.