diff --git a/src/json.c b/src/json.c
index 36d47aa..4ec4411 100644
--- a/src/json.c
+++ b/src/json.c
@@ -328,7 +328,7 @@
 	    break;
 #endif
 	case VAR_UNKNOWN:
-	    EMSG2(_(e_intern2), "json_encode_item()");
+	    internal_error("json_encode_item()");
 	    return FAIL;
     }
     return OK;