WMS Services in IMAGINE only works with geographic coordinates?
Whether or not the WMS service can be imported in Geographic Lat/lon or other projections depend on the WMS server. For example, ERDAS Apollo Server can publish WMS service in almost all EPSG projections. When using ERDAS Apollo Server to publish the WMS service, it is the user preference to determine which projection to use.
By default ERDAS Apollo Server will publish WMS in EPSG 4326 (Geographic), so if the data source is not Geographic, Apollo Server will reproject the WMS service to Geographic. If you choose UTM for your WMS service when you publish it, then Apollo Server will reproject this WMS service to UTM (if the data source is not in UTM).
WMS/WCS support has been added into IMAGINE raster format Dll framework, so you can also request WMS/WCS service inside IMAGINE products. For example, When client (I.e, IMAGINE/LPS) send request to your WMS service, Apollo Server will send map back in the Projection system you defined.