diff --git a/Misc/ACKS b/Misc/ACKS
index e04677e..1a094a1 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -633,6 +633,7 @@
 Mike Meyer
 Steven Miale
 Trent Mick
+Tom Middleton
 Stan Mihai
 Stefan Mihaila
 Aristotelis Mikropoulos
diff --git a/Misc/NEWS b/Misc/NEWS
index 5ede324..454a70c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -98,6 +98,9 @@
 Library
 -------
 
+- Issue #12288: Consider '0' and '0.0' as valid initialvalue
+  for tkinter SimpleDialog.
+
 - Issue #15489: Add a __sizeof__ implementation for BytesIO objects.
   Patch by Serhiy Storchaka.