The steps for running multiple copies of 4D Server on a single machine on OS X are the same as on OS 9 with one exception. Under OS 9.x, the modified tcp.opt file would simply be placed at the same level as the 4D server application. This still holds true for Mac OS X; however, under OS X, because of the concept of package contents, the modified tcp.opt file would need to be placed in the "MacOSClassic" folder.

Here are the specific steps:

1. While pressing the Control key, click on the 4D Server icon and select Show package contents from the contextual menu that is displayed.
2. Once the window opens, double-click and open the "contents" folder. Inside the "contents" folder, open the "MacOSClassic" folder and then place the modified tcp.opt inside it.