Crashing when starting game

[bubblesayoyo]

So i believe everything installed right, launched the..well launcher and it dl'ed everything and I get the Mojang screen. When i go to single player and load my save it simulates...yadayada then crashes. Here is the last of my log...

[15:44:41] [sEVERE] java.lang.ClassCastException: ic2.common.TileEntitySolarGenerator cannot be cast to gq

[15:44:41] [sEVERE] at rp.a(BlockChest.java:374)

[15:44:41] [sEVERE] at vq.m(World.java:682)

[15:44:41] [sEVERE] at vq.j(World.java:665)

[15:44:41] [sEVERE] at ic2.common.TileEntityElectricBlock.k_(TileEntityElectricBlock.java:177)

[15:44:41] [sEVERE] at vq.m(World.java:1574)

[15:44:41] [sEVERE] at net.minecraft.client.Minecraft.k(Minecraft.java:1552)

[15:44:41] [sEVERE] at net.minecraft.client.Minecraft.x(Minecraft.java:698)

[15:44:41] [sEVERE] at net.minecraft.client.Minecraft.run(Minecraft.java:638)

[15:44:41] [sEVERE] at java.lang.Thread.run(Thread.java:680)

Any ideas?!?!

EDIT: I can create a new world just fine. So it must be something in my old save file....

[Jay?]

Old saves are not compatible with Technic V6

[bubblesayoyo]

thanks, all i needed to know. just couldn't find it written newhere