Good thing that you happened to ask that BBS, was a good reminder since I pondered the same thing. And actually thought about Javasorc too. Too many hours in the MFO obviously, if my mind starts to wonder towards such builds
What Javelin you were thinking to use, if I may ask?
Haven't really thought it through at all, but here are my initial thoughts, which probably have big errors:
What javelin to use? This is the big question, and the most difficult IMO, because the biggest problem will be attack speed.
1. The sorc can't use Amazon-only javelins, and there are hardly ANY unique javelins in D2. No normal or exceptional at all, and only 3 elites. The fastest of those is Demon's Arch, IIRC, but it is a slow base item.
2. No runewords, and no socketing at all. That eliminates the idea of filling something with Shaels.
So, the best bet would probably be some really fast rare javelin of the Winged Harpoon or Hyperion Javelin class with "of quickness" (40 IAS mod) and "replenishes quantity". Damage doesn't really matter since that will come completely from enchant / dreams. I suppose one could just shop two stacks of "of quickness" javelins, but replenishes quantity can't spawn at the same time on a blue, can it? So it seems we may be reduced to picking up and IDing yellow javs...
Anyway, with 40 IAS Winged Harpoon or Hyperion Javelin, we still need 85% off-weapon IAS to hit max IAS (9 fps) if we want to use Infinity on the merc and not Faith... which we probably do. For the record, just checked and Demon's Arch can only hit 11 fps at 85 IAS.
EDIT: And forget using Andariel's or M'avina's to get all that IAS because Dream is already in that slot! So Hlords, Treachery, LoH it is.
Boots?
Rings - SoJ/BKWB
Belt - Razortail for piercing
EDIT: Also, I wasn't able to find anyone making a Mat / Build thread for a Javasorc ever. So even though it seems like a simple idea to have a dual-dream sorc that mimics the Lightning Javazon, it apparently has only rarely been done.