Some system-specific information can be changed after your system boots by running /sbin/set_parms. This is used to set an individual system parameter or all of the system parameters that would be set at boot time. /sbin/set_parms takes any of several arguments, depending on what you would like to configure (or re-configure):
hostname -- set / change hostname.
date_time -- set / change date and time.
timezone -- set / change time zone.
root_passwd -- set / change the root password.
ip_address -- set / change IP (Inernet Protocol) address.
addl_network -- set / change networking configuration (i.e., configure subnet mask, domain name service [DNS], network information service [NIS]).
initial -- this takes you through the entire Q&A session you would go through at system boot time.
In your case, you would run the command with the "date_time" argument: /sbin/set_parms date_time. Fill in the blanks and select OK to accept your changes.
p.s. You might have to set your display (e.g., export DISPAY=your_IP_address:0.0) if you prefer the GUI; otherwise, you get the command line interface.
