diff --git a/src/main/java/org/olat/restapi/group/LearningGroupWebService.java b/src/main/java/org/olat/restapi/group/LearningGroupWebService.java
index f719b2927aa865fef39f15ce80417034093e11d4..c1d3f3ff1d773947764729e60c461bc0480abc61 100644
--- a/src/main/java/org/olat/restapi/group/LearningGroupWebService.java
+++ b/src/main/java/org/olat/restapi/group/LearningGroupWebService.java
@@ -380,6 +380,19 @@ public class LearningGroupWebService {
 		}
 	}
 	
+	@PUT
+	@Path("{groupKey}/configuration/tools/calendar")
+	public Response putGroupCalendar(@PathParam("groupKey") Long groupKey, @Context HttpServletRequest request) {
+		final BusinessGroupService bgs = CoreSpringFactory.getImpl(BusinessGroupService.class);
+		BusinessGroup bg = bgs.loadBusinessGroup(groupKey);
+		if(bg == null) {
+			return Response.serverError().status(Status.NOT_FOUND).build();
+		}
+		CollaborationTools tools = CollaborationToolsFactory.getInstance().getOrCreateCollaborationTools(bg);
+		tools.setToolEnabled(CollaborationTools.TOOL_CALENDAR, true);
+		return Response.ok().build();
+	}
+	
 	@POST
 	@Path("{groupKey}/configuration")
 	public Response postGroupConfiguration(@PathParam("groupKey") Long groupKey, final GroupConfigurationVO group, @Context HttpServletRequest request) {