Tomcat: What is the criterion for the "Thread" column to appear on the "Connectors" page of the Probe?

Question

Hello, I would like to know what should be done so that the "Thread" column appears on the screen "Connectors" of the obe, this column appears normally in my installation of Tomcat 6.0 + Probe 2.3.3, but when using the same settings on another machine with Tomcat 6.0 + Probe 2.3.3, this column does not appear.

EDIT: The machine that works, runs Windows with java 1.6.0_18-B07. The machine that doesn’t work, runs Linux with java 1.6.0_18-B07.

Any help will be appreciated, thanks in advance.