Here is the problem I am facing.
We have our Web app server in one time zone EST and our database server on another time zone CST. There is a requirement that when a record is updated the timestamp value for the 'modified_date' column needs to be the system time of the database server. This is essential because of some dependancies on other applications that use the database.

Since we are using hibernate the java object being updated is having a 'new Date()' assigned to the "modified_date' variable in it.

What should I do to the object/hibernate mapping/code so that database server system timestamp gets entered for the record when the object is updated(basically when update is called).

One way to do it would be to make a custom UserType that acts like a timestamp, but uses the Locale of your database server. I've done something similar for a field that uses a timestamp format unlike anything that's built-in.