diff --git a/examples/minimal.json b/examples/minimal.json
index 78defdc..6664fb3 100644
--- a/examples/minimal.json
+++ b/examples/minimal.json
@@ -2,26 +2,44 @@
     "members":{
         "root":{
             "_name": "root",
+            "parent": "admin",
             "tasks": [
                 {
                     "class": "storage/logger",
-                    "type": [ "ok", "warning", "error" ],
+                    "type": [ "ok" ],
                     "args": { "directory": "/tmp/", "file": "data.log" }
                 }
             ]
+        },
+        "admin":{
+            "_name": "admin",
+            "tasks": [
+                {
+                    "class": "alert/mail",
+                    "type": [ "ok", "warning", "error" ],
+                    "args": { "host": "localhost",
+                              "port": 25,
+                              "sender": "linspector@linspector.org",
+                              "username": "",
+                              "password": "",
+                              "rcpt": "hanez@linspector.org"
+                    }
+                }
+            ]
         }
     },
     "periods": {
         "fast": { "seconds": 15 },
-        "medium": { "seconds": 120 },
-        "slow": { "seconds": 480 }
+        "medium": { "seconds": 60 },
+        "slow": { "seconds": 480 },
+        "now": {"date": "2013-12-29 00:09:00"}
     },
     "hostgroups":{
         "a":{
             "members": ["root"],
-            "hosts": [ "a"],
+            "hosts": [ "151.217.0.0/16"],
             "services":[
-                { "class": "etc/dummy", "args": { "sleep": 1, "fail": true }, "periods": ["fast"], "threshold": 1 }
+                { "class": "net/tcpconnect", "args":{ "port": 80 }, "periods": ["now"], "threshold": 1 }
             ]
         }
     },
diff --git a/linspector/config/periods.py b/linspector/config/periods.py
index c25d46d..80fd8c8 100644
--- a/linspector/config/periods.py
+++ b/linspector/config/periods.py
@@ -19,6 +19,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 """
 
 from logging import getLogger
+from apscheduler.util import convert_to_datetime
 
 logger = getLogger(__name__)
 
@@ -48,7 +49,7 @@ class IntervalPeriod(Period):
         
     def createJob(self, scheduler, jobInfo, func, **kwargs):
         start_date = self.start_date
-        if kwargs["start_date"]:
+        if "start_date" in kwargs:
             start_date = kwargs["start_date"]
 
         return scheduler.add_interval_job(func, weeks=self.weeks, hours=self.hours, minutes=self.minutes,
@@ -80,7 +81,8 @@ class CronPeriod(Period):
         
     def createJob(self, scheduler, jobInfo, func, **kwargs):
         start_date = self.start_date
-        if kwargs["start_date"]:
+
+        if "start_date" in kwargs:
             start_date = kwargs["start_date"]
 
         return scheduler.add_cron_job(func, year=self.year, month=self.month, day=self.day, week=self.week,
@@ -100,6 +102,12 @@ class DatePeriod(Period):
         
     def createJob(self, scheduler, jobInfo, func, **kwargs):
         try:
+            if "start_date" in kwargs:
+                earliest = kwargs["start_date"]
+                date = convert_to_datetime(self.date)
+                if date < earliest:
+                    self.date = earliest
+
             return scheduler.add_date_job(func=func, date=self.date, args=[jobInfo])
         except Exception, e:
-            return None
\ No newline at end of file
+            logger.error("exception while creating job out of DatePeriod!\n%s" % e)
\ No newline at end of file