java.lang.OutOfMemoryError: PermGen space
You need to allocate more memory for the JVM to work, in your launch configuration for your second Eclipse go to the Arguments tab and in the VM Arguments section, specify the maximum permgen size. It should look like this: "-Xms256m -Xmx2048m -XX:MaxPermSize=512m". For additional information, have a look here on the Eclipse wiki.
If you find this problem with your first Eclipse instance, you should tweak the permgen size in your eclipse.ini file located in your Eclipse installation folder. For more information about those settings, have a look here.