What is the best way to design database field for Date/Time when the server is in a different time zone from the client?

Hi
I want to design a date field that will be used by different clients. The clients will write queries involving relational operators such as (=, >, etc.)
The database server sits in different time zone from the clients.
The date value comes from the client's machine.
In fact each client may be in a separate time zone and hence each will have a different time value.
What is the best way to design database field for Date/Time when the server is in a different time zone from the client (I can't use triggers).
My current plan is to store the date/time on the server according to a fixed time zone (say GMT) and then ask each client to pass their local time and their time zone with a converted time value (in GMT) to match the zone on the server. Is there a better way?
Thanks.
EK
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