diff --git a/ChangeLog b/ChangeLog
index 7dea592d60..ab9e1ea73a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -27,6 +27,9 @@ Changes in version 0.1.2.6-alpha - 2007-??-??
   o Minor bugfixes:
     - Restore a warning message if we accidentally resolve an address that
       we weren't planning to resolve.
+    - Prevent an (unlikely) bug on 32-bit architectures that could make
+      directories send 503s incorrectly when BandwidthBurst plus 2 times
+      BandwidthRate was over to 2 GB.
 
 
 Changes in version 0.1.2.5-alpha - 2007-01-06
diff --git a/src/or/connection.c b/src/or/connection.c
index f42182ba6f..e4a03ac61b 100644
--- a/src/or/connection.c
+++ b/src/or/connection.c
@@ -1183,9 +1183,9 @@ global_write_bucket_low(size_t attempt, int priority)
 
   if (priority == 1) { /* old-style v1 query */
     /* Could we handle *two* of these requests within the next two seconds? */
-    /* XXX012 make this robust against overflows */
-    if (global_write_bucket + 2*(int)(get_options()->BandwidthRate) <
-        2*(int)attempt)
+    int64_t can_write = (int64_t)global_write_bucket
+      + 2*get_options()->BandwidthRate;
+    if (can_write < 2*(int64_t)attempt)
       return 1;
   } else { /* v2 query */
     /* no further constraints yet */