diff --git a/src/keyevents.c b/src/keyevents.c
index 577860f2e5bab4241964ae0fcd222cbf3c00e489..a3ab4d344f4f85fd7075ee8bb9d5058cc37c0cf9 100644
--- a/src/keyevents.c
+++ b/src/keyevents.c
@@ -298,18 +298,23 @@ feh_event_handle_keypress(XEvent * ev)
         winwidget_render_image(winwid, 0, 0);
         break;
      case XK_KP_Add:
+        /* erroneously recognized as '+' in the *kbuf switch. Work around this. */
+        len = 0;
         winwid->zoom = winwid->zoom * 1.25;
         winwidget_render_image(winwid, 0, 0);
         break;
      case XK_KP_Subtract:
+        len = 0;
         winwid->zoom = winwid->zoom * 0.75;
         winwidget_render_image(winwid, 0, 0);
         break;
      case XK_KP_Multiply:
+        len = 0;
         winwid->zoom = 1;
         winwidget_render_image(winwid, 0, 0);
         break;
      case XK_KP_Divide:
+        len = 0;
         feh_calc_needed_zoom(&winwid->zoom, winwid->im_w, winwid->im_h, winwid->w, winwid->h);
         winwidget_render_image(winwid, 0, 0);
         break;