I think your path should be the windows path since that server is running on windows.
instead of "/athlon_g/Program Files/Common Files/Borland Shared/Data/EMPLOYEE.GDB" you should have
"G:\Program Files\Common Files\Borland Shared\Data\EMPLOYEE.GDB"
Your path is a linux path, this would work if you would like to use that file on localhost, however i think you need a trick/setting to use a network file as local with FB/IB.
OFF-TOPIC: change the .gdb extension to .idb or some other extension since .gdb is a reserved windows extension and will reduce the speed of your server, read more on ibphoenix website.