Opening multiple instances of Eclipse on mac.

Double clicking on eclipse icon always opens the same instance on MAC. To solve this, you can open terminal (Command-Space to launch spotlight. Type in terminal and click on the top hit/Terminal link).
Cd to the place where you unzipped eclipse.
For .e.g, Eclipse/Eclipse.app/Contents/MacOS/


Then run eclipse &. (& makes sure you run eclipse in background, so that you can kill the terminal window.).