Blizzard has revealed info about their next patch "v1.10" for Diablo II.. Here is the cut and past:

We’ll be adding many new Horadric Cube recipes to Diablo II with the upcoming 1.10 patch. Some of the new recipes allow you to upgrade your Unique weapons. For instance, 1 Ral Rune + 1 Sol Rune + 1 Perfect Emerald + 1 Normal Unique Weapon results in an Exceptional version of that weapon with the same Unique Item bonuses. Using this recipe, an Axe will be transformed into a Cleaver! This is useful for upgrading the damage of your Unique Weapons. You can use another recipe to upgrade to the Elite version: 1 Lum Rune + 1 Pul Rune + 1 Perfect Emerald + Exceptional Unique Weapon results in the Elite version of that weapon with the same Unique Item bonuses. Using these new formulae, players can create new special versions of Unique items that were not previously possible. Players can then further customize these weapons by adding a socket to them and their own favorite gem, jewel, or rune.

Although we do not have a release date set for this patch, we are working hard to get it out as soon as possible.
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