How to create wlfullclient.jar over weblogic installation?

First position within the folder of weblogic home:

cd WL_HOME/server/lib

Next to create de jar with the following execution parameter:

java -jar wljarbuilder.jar

Now you will have wlfullclient.jar created in the folder.

Important links:
http://docs.oracle.com/cd/E24329_01/web.1211/e24378/jarbuilder.htm#SACLT421