Imports a package to a domain.
void importPackage(String fileName, Boolean overwrite) throws SUPAdminException;
If successful, returns silently. If unsuccessful, returns SUPAdminException.
supDomain.importPackage("<exported package file name>", true);
You can only import package into the same domain as the one you exported from. The API requires that the domain where the package was exported from exists on the server when the import is done. Also, you are required to create domains in the same order in both the export and import server environments, which ensures that an internal ID assigned to the domain in both environment matches.
You can verify the internal ID assigned to a domain by looking at the prefix used in the package folder in the zip.