diff --git a/scm-webapp/src/main/java/sonia/scm/api/NotSupportedExceptionMapper.java b/scm-webapp/src/main/java/sonia/scm/api/NotSupportedExceptionMapper.java
new file mode 100644
index 0000000000..33e1e368d7
--- /dev/null
+++ b/scm-webapp/src/main/java/sonia/scm/api/NotSupportedExceptionMapper.java
@@ -0,0 +1,31 @@
+package sonia.scm.api;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.MDC;
+import sonia.scm.api.v2.resources.ErrorDto;
+import sonia.scm.web.VndMediaType;
+
+import javax.ws.rs.NotSupportedException;
+import javax.ws.rs.core.Response;
+import javax.ws.rs.ext.ExceptionMapper;
+import javax.ws.rs.ext.Provider;
+
+@Provider
+public class NotSupportedExceptionMapper implements ExceptionMapper<NotSupportedException> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(NotSupportedExceptionMapper.class);
+
+  @Override
+  public Response toResponse(NotSupportedException exception) {
+    LOG.debug("illegal media type");
+    ErrorDto error = new ErrorDto();
+    error.setTransactionId(MDC.get("transaction_id"));
+    error.setMessage("illegal media type");
+    error.setErrorCode("8pRBYDURx1");
+    return Response.status(Response.Status.UNSUPPORTED_MEDIA_TYPE)
+      .entity(error)
+      .type(VndMediaType.ERROR_TYPE)
+      .build();
+  }
+}