24 hour clock, for client, or is it server ..... howto?

I have my machine in 24 hour clock. Chats inside Spark 2.5.8 on OS X (Leopard) using openFire 3.5.0 Ent Ed server to another (internal user) user also using Spark, shows the timestamps running down the left side of the trsacript in 12 hour clock (AM/PM time).

Since the USA is like the last nation on the planet to use 24 hour clock (and please please plase do not call it military time, I harbor powerful disdain for the military) this is a small issue, not huge, but growing, issue for us especially as more and more people travel more and more these days.

If a box that one could mark with a tick were added to the “Language and Time” screen in the server admin window, that’d be way kewl!

Any and all advice on how to set this is most appreciated.