diff --git a/docs/rh-log.txt b/docs/rh-log.txt
index b2733cb1aa..c939d9437b 100644
--- a/docs/rh-log.txt
+++ b/docs/rh-log.txt
@@ -1,4 +1,8 @@
-August 3, 2009  (Changes by Graf Zahl)
+August 4, 2009
+- Fixed: FWeaponSlot::PickWeapon() wrapped around improperly when the starting
+  value for i was 0.
+
+August 3, 2009  (Changes by Graf Zahl)
 - Added kgsws's SummonActor enhancement and bumped netgame and demo versions
   because this submission changes an existing command.
 
diff --git a/src/g_shared/a_weapons.cpp b/src/g_shared/a_weapons.cpp
index 152a4a110a..d4fb4ec5ce 100644
--- a/src/g_shared/a_weapons.cpp
+++ b/src/g_shared/a_weapons.cpp
@@ -776,9 +776,9 @@ AWeapon *FWeaponSlot::PickWeapon(player_t *player)
 				 player->ReadyWeapon->SisterWeapon != NULL &&
 				 player->ReadyWeapon->SisterWeapon->GetClass() == Weapons[i].Type))
 			{
-				for (j = (unsigned)(i - 1) % Weapons.Size();
+				for (j = (i == 0 ? Weapons.Size() - 1 : i - 1);
 					j != i;
-					j = (unsigned)(j + Weapons.Size() - 1) % Weapons.Size())	// + Weapons.Size is to avoid underflows
+					j = (j == 0 ? Weapons.Size() - 1 : j - 1))
 				{
 					AWeapon *weap = static_cast<AWeapon *> (player->mo->FindInventory(Weapons[j].Type));