During testing the BETA (RO_VERSION = '9.4.0.1361') we found a bug in the TRORttiClientCache.GetProperties_OriginalSort method.
This bug results to errors when the service simultaneously serves both SOAP and REST clients. The reason is that these clients expect different orders of serialized properties (one is RTTI-based and another is alphabetically sorted).
We prepared a patch for the method that solves the issue (GetProperties_OriginalSort.pas). We hope that it will help you.