diff --git a/netwerk/cache/nsCacheService.cpp b/netwerk/cache/nsCacheService.cpp
index 4bdef33c527..ca196599f8f 100644
--- a/netwerk/cache/nsCacheService.cpp
+++ b/netwerk/cache/nsCacheService.cpp
@@ -173,8 +173,9 @@ public:
                                       uint32_t currentSize,
                                       bool shouldUseOldMaxSmartSize);
 
-private:
     bool                    PermittedToSmartSize(nsIPrefBranch*, bool firstRun);
+
+private:
     bool                    mHaveProfile;
     
     bool                    mDiskCacheEnabled;
@@ -1595,28 +1596,27 @@ public:
         if (!nsCacheService::gService || !nsCacheService::gService->mObserver)
             return NS_ERROR_NOT_AVAILABLE;
 
-        nsDisableOldMaxSmartSizePrefEvent::DisableOldMaxSmartSizePref(true);
-        return NS_OK;
-    }
-
-    static void DisableOldMaxSmartSizePref(bool async)
-    {
         nsCOMPtr<nsIPrefBranch> branch = do_GetService(NS_PREFSERVICE_CONTRACTID);
         if (!branch) {
-            return;
+            return NS_ERROR_NOT_AVAILABLE;
         }
 
         nsresult rv = branch->SetBoolPref(DISK_CACHE_USE_OLD_MAX_SMART_SIZE_PREF, false);
         if (NS_FAILED(rv)) {
             NS_WARNING("Failed to disable old max smart size");
-            return;
+            return rv;
         }
 
-        if (async) {
-            nsCacheService::SetDiskSmartSize();
-        } else {
-            nsCacheService::gService->SetDiskSmartSize_Locked();
+        nsCacheService::SetDiskSmartSize();
+
+        if (nsCacheService::gService->mObserver->PermittedToSmartSize(branch, false)) {
+            rv = branch->SetIntPref(DISK_CACHE_CAPACITY_PREF, MAX_CACHE_SIZE);
+            if (NS_FAILED(rv)) {
+                NS_WARNING("Failed to set cache capacity pref");
+            }
         }
+
+        return NS_OK;
     }
 };
 
@@ -1630,11 +1630,9 @@ nsCacheService::MarkStartingFresh()
 
     gService->mObserver->SetUseNewMaxSmartSize(true);
 
-    if (NS_IsMainThread()) {
-        nsDisableOldMaxSmartSizePrefEvent::DisableOldMaxSmartSizePref(false);
-    } else {
-        NS_DispatchToMainThread(new nsDisableOldMaxSmartSizePrefEvent());
-    }
+    // We always dispatch an event here because we don't want to deal with lock
+    // reentrance issues.
+    NS_DispatchToMainThread(new nsDisableOldMaxSmartSizePrefEvent());
 }
 
 nsresult