I still don't have an smv (apparently my version of snes9x hates me?), but I managed to replicate the feat today. Additionally, I found a save state from the first time I tried and succeeded. If you load them in order, you can see how I do it, although I must apologize for not having states of every bomb; my method of doing this involves using two save states and alternating between them after each bomb so that I don't have to start over from the beginning. As a result, only the last two are left.
I should mention that there was something I was forgetting in my previous descriptions. You guys were right; the bomb counter timing prevents you from hitting the final two bombs unless you cheat a little. After the second-to-last bomb (metroid3.005 below), you lay the final bomb ALMOST at the top of the jump, but not quite.
tricky part
The instant that you lay it, you have to uncurl from the morph ball, then curl back up. This buys you a couple frames of being motionless in midair so that you can catch the second-to-last and last bombs. You must use this technique to "get it" for all of the following save states:
http://darctek.ath.cx:8003/metroid3.003 (original attempt; lay two bombs, each at the instant that the bomb counter refills)
jigsaw style: lay bombs to "connect" the save states
http://darctek.ath.cx:8003/metroid3.004 (just out of the lava)
http://darctek.ath.cx:8003/metroid3.005 (completely out of the lava)
http://darctek.ath.cx:8003/metroid3.006 (hold right to bounce onto the ledge)
For each one of these, you should be laying bombs as soon as the counter refills. If you have trouble playing connect the dots let me know and I'll try to get a couple more states up.
This clearly shows your positioning from two different spots and timings at the top of the lava, both of which are feasible and tested by me over the past twenty minutes.
