Have the answer. Thanks to Eric Havill @ Cisco.
Edit the "/etc/sysconfig/i18n" file in the Linux shell of CPI.
Add LANG="en_GB.UTF-8" to the file and comment out the other one.
The file should now be something like this.
LANG="en_GB.UTF-8"
##LANG="en_US.UTF-8"
SYSFONT="latarcyrheb-sun16"
As you can imagine the US is 12hr and GB is 24hr.
Now you need to restart the server for the settings to take effect.
