Fireballs no longer do damage at 0 explosive power

In the 1.8.x versions, when a fireball was summoned using /summon and with an explosive power of 0, it would do damge upon impact. Just not explosive damage. But in 1.9 this no longer works. I liked it better the way it was (I am a map maker. See "http://www.minecraftmaps.com/pvp-maps/fireball-pvp-2-vertical-warfare") I used this feature to make an awesome shooter, but now when the fireball is summoned using a clock with the command "/execute @e[type=Snowball] ~ ~ ~ summon Fireball ~ ~3 ~

{direction:[0.0,0.0,0.0],ExplosionPower:0}

" the fireball does no damage. Please fix this!