Steps to reproduce:
1) Install Liferay Bundle with Tomcat and set two databases (lportal1 and lportal2) on your local MySQL
2) Use attached portal-ext.properties
3) Put the attached shard-data-source-spring-ext.xml into $TOMCAT_HOME/webapps/ROOT/WEB-INF/classes/META-INF/
4) Start Liferay and create a new Portal Instance
5) Access this new instance and create a new user
6) Change the password of this newly created user
7) Make a search for active/inactive user
8) In Mysql do "use lportal2; select emailAddress,status from User_;"
9) See the status for the new user
The same issue was not reproduced with the Default Portal Intance.
The same issue was not reproduced when not using shard, even on new Portal Instances.
Also, after create the user and before change his password, note that when pressing the "Action" button, you will see "Activate" instead of "Deactivate", then if you want to deactivate this user, you'll have to activate it first.