diff --git a/configure.ac b/configure.ac
index a81fa8e7..80730abd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -84,7 +84,7 @@ AC_SUBST(CORE_DATA_DIR)
 AC_ARG_WITH([guiconfdir],
 	    [AS_HELP_STRING([--with-guiconfdir=dir],
 			    [specify GUI configuration directory])],
-	    [CORE_GUI_CONF_DIR="$with_guiconfdir"], 
+	    [CORE_GUI_CONF_DIR="$with_guiconfdir"],
 	    [CORE_GUI_CONF_DIR="\${HOME}/.core"])
 AC_SUBST(CORE_GUI_CONF_DIR)
 AC_ARG_ENABLE([gui],
@@ -143,6 +143,8 @@ if test "x$enable_daemon" = "xyes" ; then
   AC_CHECK_PROG(mount_path, mount, $as_dir, no, $SEARCHPATH)
   AC_CHECK_PROG(umount_path, umount, $as_dir, no, $SEARCHPATH)
   AC_CHECK_PROG(convert, convert, yes, no, $SEARCHPATH)
+  AC_CHECK_PROG(ovs_vs_path, ovs-vsctl, $as_dir, no, $SEARCHPATH)
+  AC_CHECK_PROG(ovs_of_path, ovs-ofctl, $as_dir, no, $SEARCHPATH)
 fi
 
 #AC_CHECK_PROG(dia, dia, yes, no)
diff --git a/daemon/core/api/coreapi.py b/daemon/core/api/coreapi.py
index b59446ef..096b3568 100644
--- a/daemon/core/api/coreapi.py
+++ b/daemon/core/api/coreapi.py
@@ -24,7 +24,7 @@ from core.enumerations import MessageTypes
 from core.enumerations import NodeTlvs
 from core.enumerations import RegisterTlvs
 from core.enumerations import SessionTlvs
-from core.misc import log, structutils
+from core.misc import structutils
 from core.misc.ipaddress import IpAddress
 from core.misc.ipaddress import MacAddress
 
diff --git a/daemon/core/constants.py.in b/daemon/core/constants.py.in
index 0aa8ea5f..674c0dc7 100644
--- a/daemon/core/constants.py.in
+++ b/daemon/core/constants.py.in
@@ -17,3 +17,5 @@ VIMAGE_BIN              = "@vimage_path@/vimage"
 QUAGGA_STATE_DIR        = "@CORE_STATE_DIR@/run/quagga"
 MOUNT_BIN               = "@mount_path@/mount"
 UMOUNT_BIN              = "@umount_path@/umount"
+OVS_BIN                 = "@ovs_vs_path@/ovs-vsctl"
+OVS_FLOW_BIN            = "@ovs_of_path@/ovs-ofctl"
diff --git a/daemon/core/emane/tdma.py b/daemon/core/emane/tdma.py
index b5f01618..e12eb9b6 100644
--- a/daemon/core/emane/tdma.py
+++ b/daemon/core/emane/tdma.py
@@ -3,6 +3,7 @@ tdma.py: EMANE TDMA model bindings for CORE
 """
 
 from core import emane
+from core import logger
 from core.emane.emanemodel import EmaneModel
 from core.emane.universal import EmaneUniversalModel
 from core.enumerations import ConfigDataTypes
@@ -14,10 +15,9 @@ class EmaneTdmaModel(EmaneModel):
 
     # model name
     name = "emane_tdma"
-    if emane.VERSION >= emane.EMANE101:
-        xml_path = "/usr/share/emane/xml/models/mac/tdmaeventscheduler"
-    else:
-        raise Exception("EMANE TDMA requires EMANE 1.0.1 or greater")
+    xml_path = "/usr/share/emane/xml/models/mac/tdmaeventscheduler"
+    if emane.VERSION < emane.EMANE101:
+        logger.error("EMANE TDMA requires EMANE 1.0.1 or greater")
 
     # MAC parameters
     _confmatrix_mac = [
diff --git a/daemon/core/service.py b/daemon/core/service.py
index 66d45bf9..f60059f0 100644
--- a/daemon/core/service.py
+++ b/daemon/core/service.py
@@ -135,12 +135,15 @@ class ServiceManager(object):
         for module_name in module_names:
             import_statement = "%s.%s" % (base_module, module_name)
             logger.info("importing custom service module: %s", import_statement)
-            module = importlib.import_module(import_statement)
-            members = inspect.getmembers(module, lambda x: _is_service(module, x))
-            for member in members:
-                clazz = member[1]
-                clazz.on_load()
-                cls.add(clazz)
+            try:
+                module = importlib.import_module(import_statement)
+                members = inspect.getmembers(module, lambda x: _is_service(module, x))
+                for member in members:
+                    clazz = member[1]
+                    clazz.on_load()
+                    cls.add(clazz)
+            except:
+                logger.exception("unexpected error during import, skipping: %s", import_statement)
 
 
 class CoreServices(ConfigurableManager):
diff --git a/daemon/core/xml/xmldeployment.py b/daemon/core/xml/xmldeployment.py
index 91f22abb..a1b387ad 100644
--- a/daemon/core/xml/xmldeployment.py
+++ b/daemon/core/xml/xmldeployment.py
@@ -7,7 +7,6 @@ from core import emane
 from core import logger
 from core.enumerations import NodeTypes
 from core.misc import ipaddress
-from core.misc import log
 from core.misc import nodeutils
 from core.netns import nodes
 from core.xml import xmlutils
diff --git a/daemon/setup.py b/daemon/setup.py
index 03006589..221e257f 100644
--- a/daemon/setup.py
+++ b/daemon/setup.py
@@ -25,7 +25,7 @@ setup(name="core-python",
           "core.xml",
       ],
       install_requires=[
-          "enum34"
+          "enum34",
           "logzero"
       ],
       setup_requires=[