First, change DefaultPermissionsModule so it returns the correct name...

... Then, make sure we also check the old-style module stack before we throw a tantrum

OpenSim/Region/Application/OpenSimBase.cs

@@ -356,12 +356,23 @@ namespace OpenSim
                 foreach (string s in m_permsModules)
                 {
                     if (!scene.RegionModules.ContainsKey(s))
+                    {
+                        bool found = false;
+                        foreach (IRegionModule m in modules)
+                        {
+                            if (m.Name == s)
+                            {
+                                found = true;
+                            }
+                        }
+                        if (!found)
                         {
                             m_log.Fatal("[MODULES]: Required module " + s + " not found.");
                             Environment.Exit(0);
                         }
                     }
                 }
+            }
 
             scene.SetModuleInterfaces();
 // First Step of bootreport sequence

OpenSim/Region/CoreModules/World/Permissions/PermissionsModule.cs

@@ -402,7 +402,7 @@ namespace OpenSim.Region.CoreModules.World.Permissions
 
         public string Name
         {
-            get { return "PermissionsModule"; }
+            get { return "DefaultPermissionsModule"; }
         }
 
         public bool IsSharedModule