diff --git a/py/mock.py b/py/mock.py
index d5afbbe..a48ffe2 100755
--- a/py/mock.py
+++ b/py/mock.py
@@ -425,9 +425,13 @@ def main(ret):
     if options.configdir:
         config_path = options.configdir
 
+    # save for use in Root object
+    config_opts['config_paths'] = []
+
     # Read in the config files: default, and then user specified
     for cfg in ( os.path.join(config_path, 'site-defaults.cfg'), '%s/%s.cfg' % (config_path, options.chroot)):
         if os.path.exists(cfg):
+            config_opts['config_paths'].append(cfg)
             execfile(cfg)
         else:
             log.error("Could not find required config file: %s" % cfg)
diff --git a/py/mock/backend.py b/py/mock/backend.py
index 7d11532..6726deb 100644
--- a/py/mock/backend.py
+++ b/py/mock/backend.py
@@ -50,6 +50,7 @@ class Root(object):
         self._state_log = getLog("mock.Root.state")
 
         # config options
+        self.configs = config['config_paths']
         self.chrootuid = config['chrootuid']
         self.chrootuser = 'mockbuild'
         self.chrootgid = config['chrootgid']
diff --git a/py/mock/plugins/root_cache.py b/py/mock/plugins/root_cache.py
index 9cb0a13..5382912 100644
--- a/py/mock/plugins/root_cache.py
+++ b/py/mock/plugins/root_cache.py
@@ -61,12 +61,21 @@ class RootCache(object):
         if self.rootCacheLock is None:
             self.rootCacheLock = open(os.path.join(self.rootSharedCachePath, "rootcache.lock"), "a+")
 
-        # check cache age:
+        # check cache status
         try:
+            # see if it aged out
             statinfo = os.stat(self.rootCacheFile)
             file_age_days = (time.time() - statinfo.st_ctime) / (60 * 60 * 24)
             if file_age_days > self.root_cache_opts['max_age_days']:
+                getLog().info("root cache aged out! cache will be rebuilt")
                 os.unlink(self.rootCacheFile)
+            else:
+                # make sure no config file is newer than the cache file
+                for cfg in self.rootObj.configs:
+                    if os.stat(cfg).st_mtime > statinfo.st_mtime:
+                        getLog().info("%s newer than root cache; cache will be rebuilt" % cfg)
+                        os.unlink(self.rootCacheFile)
+                        break
         except OSError:
             pass
 