one time in 1.7.3 i was messing around with singleplayer commands, and i turned off player damage and was swimming around in some lava. i noticed there was a creeper swimming in it too, i just got a glimpse of its face. i thought it was just something else and kept swimming, but then it came right up to me and was staring at me like a passive mob, and wasnt exploding. i was on peaceful this whole time, does anybody know anything about this? btw it was naturally occuring lava.