Date field render wrong value of year

Description of problem:

Date field render wrong value of year. For example, 2014 is renderred as 14. This is not just UI issue, it pass the wrong value to backend.

How reproducible:

1. add a process variable of type java.util.Date
2. generate forms by clicking "Generate all forms"
3. Print the variable value in a script task, such as:

java.util.Date ex = (java.util.Date)kcontext.getVariable("enddate");
System.out.println(ex);

4. start a process instance and input current date

Actual results:

Wed Jun 20 16:03:52 CST 14

Expected results:

Fri Jun 20 16:03:52 CST 2014

Additional info:

This is NOT a display issue. You can see the "Wed". In fact, I tested this today which is Friday! BPMS really misfunctioned and treated it as Jun 20, 0014 which was a Wednesday 2000 years ago.