Failing to build Liferay: build-ext

I am trying to build liferay and I have following this tutorial: http://www.liferay.com/web/guest/community/wiki/-/wiki/Main/Development%20Environment%20%28Windows%29

In the step where I have to build the sources, I get a fail with this message:

Target "build-ext" does not exist in the project "protal"

开发者_运维百科

The version of Liferay I am using is 6.0.5.

Thanks in advance.

the tutorial you are referring too is for liferay version 4-5

from 6, the ext env. no longer exist, it's was replaced by the plugin sdk