If it's SMP, it is possible. (hurr durr)
Just make an iron furnace (dont create it, just make it in the crafting table) and add lapis in the middle. It'll make 4 chunkloading blocks. Now, you go to the nether, set up your rig and use the minimap to see the chunks. (press ".", go to SurfaceMap options > Show Chunk Grid). Now place a chunkloading block in each chunk that your rig is in. (Usually 1-2)
Now go back to the overworld, and place the teleport pipe (it has to use the same frequency as the one in the nether). Place a chunk loading block there and you're done!
Also, tell me if it works. I also need this kind of stuff. I found a huuuuuuge lava ocean and I want it for the geothermal.