In case someone stumbles upon this same issue looking for a solution, in my case the problem was that I needed to run:
And then refresh the project in eclipse. (Maybe this is the step that used to be step 5 at the time of this post, but it is now step 6.)
When i join minecraft 1.6.2 on a download of thinks lab with the weather mod installed it shows this-
"The game crashed whilst rendering entity in world Error: java.lang.ArrayIndexOutOfBoundsException: 18 Exit Code: -1"
Does anyone know what the problem is?