diff --git a/iwla.py b/iwla.py
index fd5b2ab..5e00640 100755
--- a/iwla.py
+++ b/iwla.py
@@ -683,13 +683,40 @@ class IWLA(object):
 
         return True
 
-    def start(self, _file):
+    def _reset(self):
+        reset_time = time.strptime(self.args.reset, '%m/%Y')
+
+        self.logger.info('Reset time')
+        self.logger.info(reset_time)
+
+        self.meta_infos['last_time'] = reset_time
+
+        cur_time = time.localtime()
+        year = reset_time.tm_year
+        while year < cur_time.tm_year:
+            db_path = os.path.join(conf.DB_ROOT, str(year))
+            if os.path.exists(db_path): shutil.rmtree(db_path)
+            output_path = os.path.join(conf.DISPLAY_ROOT, str(year))
+            if os.path.exists(output_path): shutil.rmtree(output_path)
+            year += 1
+        month = reset_time.tm_mon
+        while month <= cur_time.tm_mon:
+            db_path = os.path.join(conf.DB_ROOT, str(year), '%02d' % (month))
+            if os.path.exists(db_path): shutil.rmtree(db_path)
+            output_path = os.path.join(conf.DISPLAY_ROOT, str(year), '%02d' % (month))
+            if os.path.exists(output_path): shutil.rmtree(output_path)
+            month += 1
+
+    def start(self, _file, args):
+        self.args = args
         self.start_time = datetime.now()
 
         self.logger.info('==> Load previous database')
 
         self.meta_infos = self._deserialize(conf.META_PATH) or self._clearMeta()
         if self.meta_infos['last_time']:
+            if args.reset:
+                self._reset()
             self.logger.info('Last time')
             self.logger.info(self.meta_infos['last_time'])
             self.current_analysis = self._deserialize(self.getDBFilename(self.meta_infos['last_time'])) or self._clearVisits()
@@ -743,7 +770,11 @@ class FileIter(object):
             self.cur_file = None
         if not self.filenames:
             raise StopIteration()
-        self.cur_file = open(self.filenames.pop(0))
+        filename = self.filenames.pop(0)
+        if filename.endswith('gz'):
+            self.cur_file = gzip.open(filename, 'r')
+        else:
+            self.cur_file = open(filename)
 
     def next(self):
         l = self.cur_file.readline()
@@ -770,6 +801,9 @@ if __name__ == '__main__':
                         default='INFO', type=str,
                         help='Loglevel in %s, default : %s' % (['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'INFO'))
 
+    parser.add_argument('-r', '--reset', dest='reset',
+                        help='Reset analysis to a specific date (month/year)')
+
     args = parser.parse_args()
 
     # Load user conf
@@ -804,7 +838,7 @@ if __name__ == '__main__':
         sys.exit(0)
 
     if args.stdin:
-        iwla.start(sys.stdin)
+        iwla.start(sys.stdin, args)
     else:
         filename = args.file or conf.analyzed_filename
-        iwla.start(FileIter(filename))
+        iwla.start(FileIter(filename), args)
diff --git a/plugins/pre_analysis/page_to_hit.py b/plugins/pre_analysis/page_to_hit.py
index 77772bb..282f53f 100644
--- a/plugins/pre_analysis/page_to_hit.py
+++ b/plugins/pre_analysis/page_to_hit.py
@@ -19,6 +19,7 @@
 #
 
 import re
+import logging
 
 from iwla import IWLA
 from iplugin import IPlugin
@@ -64,6 +65,7 @@ class IWLAPreAnalysisPageToHit(IPlugin):
         self.hp_regexps = self.iwla.getConfValue('hit_to_page_conf', [])
         self.hp_regexps = map(lambda(r): re.compile(r), self.hp_regexps)
 
+        self.logger = logging.getLogger(self.__class__.__name__)
         return True
 
     def hook(self):
@@ -85,7 +87,7 @@ class IWLAPreAnalysisPageToHit(IPlugin):
                     # Page to hit
                     for regexp in self.ph_regexps:
                         if regexp.match(uri):
-                            #print '%s is a hit' % (uri )
+                            self.logger.debug('%s changed from page to hit' % (uri))
                             request['is_page'] = False
                             super_hit['viewed_pages'] -= 1
                             super_hit['viewed_hits'] += 1
@@ -94,7 +96,7 @@ class IWLAPreAnalysisPageToHit(IPlugin):
                     # Hit to page
                     for regexp in self.hp_regexps:
                         if regexp.match(uri):
-                            #print '%s is a page' % (uri )
+                            self.logger.debug('%s changed from hit to page' % (uri))
                             request['is_page'] = True
                             super_hit['viewed_pages'] += 1
                             super_hit['viewed_hits'] -= 1
diff --git a/plugins/pre_analysis/robots.py b/plugins/pre_analysis/robots.py
index 41c744e..d84087d 100644
--- a/plugins/pre_analysis/robots.py
+++ b/plugins/pre_analysis/robots.py
@@ -20,6 +20,7 @@
 
 import re
 import logging
+import inspect
 
 from iwla import IWLA
 from iplugin import IPlugin
@@ -66,7 +67,11 @@ class IWLAPreAnalysisRobots(IPlugin):
         return True
 
     def _setRobot(self, k, super_hit):
-        self.logger.debug('%s is a robot' % (k))
+        callerframerecord = inspect.stack()[1]
+        frame = callerframerecord[0]
+        info = inspect.getframeinfo(frame)
+
+        self.logger.debug('%s is a robot (caller %s:%d)' % (k, info.function, info.lineno))
         super_hit['robot'] = 1
 
 # Basic rule to detect robots
@@ -84,6 +89,7 @@ class IWLAPreAnalysisRobots(IPlugin):
 
             if self.robot_re.match(first_page['http_user_agent']) or\
                     self.crawl_re.match(first_page['http_user_agent']):
+                self.logger.debug(first_page['http_user_agent'])
                 self._setRobot(k, super_hit)
                 continue
 
@@ -93,6 +99,7 @@ class IWLAPreAnalysisRobots(IPlugin):
                     break
 
             if isRobot:
+                self.logger.debug(first_page['http_user_agent'])
                 self._setRobot(k, super_hit)
                 continue
 
@@ -103,6 +110,7 @@ class IWLAPreAnalysisRobots(IPlugin):
 
 # 2) pages without hit --> robot
             if not super_hit['viewed_hits']:
+                self.logger.debug(super_hit)
                 self._setRobot(k, super_hit)
                 continue