Odd physics thought problem?

Here's a tricky one. Say you had a very (very) large, spherical, empty room that was completely airtight and sealed from the outside. Hanging from the ceiling at the exact center of the room you have a Hydrogen bomb. All air is evacuated from the room so that the bomb is hanging in a complete vacuum. You detonate the bomb. So here's the tricky part: assuming that the room is large enough and able to withstand the temperature, will the room be unharmed and not blown apart due to the fact that all expanding matter will simply fill up the empty space inside the room, thus leaving the walls completely intact?