Ender Portal Frame

Ender Portal Frame is a block that can be found in strongholds as of Beta 1.9 pre-release 3. It is likely that they will tie in with The End dimension through the creation of Ender Portals. It is a non-solid block when cracked, becoming solid when repaired. They cannot be mined, however an explosion will cause them to drop as an item shaped like a Glass Pane. They have no tooltip, indicating that them dropping at all might be a bug. The player can repair a cracked Ender Portal Frame by right clicking it with an Eye of Ender.

They are found in a ring shape within a room with a pool of lava and a staircase containing a Silverfish spawner. Some are naturally cracked at random.

On jebs livestream, it was publicized that there now was another texture, and instead of using an Eye of Ender to repair a block, you now need to insert all Eyes of Ender to make the portal work.

Trivia
This is especially noticable when it gets dark.
 * The frame block cannot be moved using pistons.
 * Portals are often "guarded" by silverfish spawners.
 * Redstone circuits can NOT be passed through frame blocks.
 * Using the "Too Many Items" mod to place air portal block above ground, shows that the block emits a bright blue glow.