Knowing that an end portal frame block does not normally destroy sand, I wanted to create a spawner, spawning falling sand above it (don't laugh, I actually have a use for it). I changed a piece of falling sand to a spawner via MCEdit.

The sand, spawned by the spawner, DID get destroyed by the portal frame, as happens with most non-solid blocks.

This happened because logging out changed the sand code, and the spawner was spawning slightly different entities.
Since you need to quit a world before using MCEdit, this makes it impossible to make such a spawner.

Steps to Reproduce:
1. Place an end portal frame block in your world.
2. Place sand a few blocks above it.
3. As it starts falling, exit to the title screen.
4. Log back into your world, sand will land on the portal and get destroyed, which does not happen normally.

note: for this to work, there must not be an eye of ender in the portal frame. The same effect might happen at certain other blocks. Not tested.