Answer
ArcMap Server, at ArcIMS version 4.0.1 and after, supports layers that contain table joins where the table is accessed through ArcGIS supported OLE DB or ODBC connections.
Standalone tables (those present in the ArcMap document, but not joined to a feature class layer) are not supported. They will be dropped from the map when served.
OLE DB is not supported in ArcIMS 4.0