diff --git a/cloud/settings.py b/cloud/settings.py
index 997f224..704be8e 100644
--- a/cloud/settings.py
+++ b/cloud/settings.py
@@ -12,12 +12,16 @@ MANAGERS = ADMINS
 
 DATABASES = {
     'default': {
-        'ENGINE': 'django.db.backends.mysql', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.
-        'NAME': 'webadmin',                      # Or path to database file if using sqlite3.
-        'USER': 'webadmin',                      # Not used with sqlite3.
-        'PASSWORD': 'asjklddfjklqjf',                  # Not used with sqlite3.
-        'HOST': '',                      # Set to empty string for localhost. Not used with sqlite3.
-        'PORT': '',                      # Set to empty string for default. Not used with sqlite3.
+        'ENGINE': 'django.db.backends.mysql', # Add 'postgresql_psycopg2',
+                                              # 'mysql', 'sqlite3' or 'oracle'.
+        'NAME': 'webadmin',                   # Or path to database file if
+                                              # using sqlite3.
+        'USER': 'webadmin',                   # Not used with sqlite3.
+        'PASSWORD': 'asjklddfjklqjf',         # Not used with sqlite3.
+        'HOST': '',                           # Set to empty string for localhost.
+                                              # Not used with sqlite3.
+        'PORT': '',                           # Set to empty string for default.
+                                              # Not used with sqlite3.
     }
 }
 
diff --git a/cloud/urls.py b/cloud/urls.py
index b29bee8..a488b8c 100644
--- a/cloud/urls.py
+++ b/cloud/urls.py
@@ -8,22 +8,29 @@ import firewall.views
 #import store.views
 
 urlpatterns = patterns('',
-     url(r'^admin/doc/', include('django.contrib.admindocs.urls')),
-     url(r'^admin/', include(admin.site.urls)),
-     url(r'^$', 'one.views.home', name='home'),
-     url(r'^login/$', 'school.views.login', name='login'),
-     url(r'^logout/$', 'school.views.logout', name='logout'),
-     url(r'^vm/new/(?P<template>\d+)/$', 'one.views.vm_new', name='vm_new'),
-     url(r'^vm/show/(?P<iid>\d+)/$', 'one.views.vm_show', name='vm_show'),
-     url(r'^vm/delete/(?P<iid>\d+)/$', 'one.views.vm_delete', name='vm_delete'),
-     url(r'^vm/stop/(?P<iid>\d+)/$', 'one.views.vm_stop', name='vm_stop'),
-     url(r'^vm/resume/(?P<iid>\d+)/$', 'one.views.vm_resume', name='vm_resume'),
-     url(r'^vm/power_off/(?P<iid>\d+)/$', 'one.views.vm_power_off', name='vm_power_off'),
-     url(r'^vm/restart/(?P<iid>\d+)/$', 'one.views.vm_restart', name='vm_restart'),
-     url(r'^vm/port_add/(?P<iid>\d+)/$', 'one.views.vm_port_add', name='vm_port_add'),
-     url(r'^vm/port_del/(?P<iid>\d+)/(?P<proto>tcp|udp)/(?P<public>\d+)/$', 'one.views.vm_port_del', name='vm_port_del'),
-     url(r'^reload/$', 'firewall.views.reload_firewall', name='reload_firewall'),
-     url(r'^fwapi/$', 'firewall.views.firewall_api', name='firewall_api'),
-     url(r'^store/$', 'store.views.index', name='store_index'),
-     url(r'^store/top/$', 'store.views.toplist', name='store_top'),
+    url(r'^admin/doc/', include('django.contrib.admindocs.urls')),
+    url(r'^admin/', include(admin.site.urls)),
+    url(r'^$', 'one.views.home', name='home'),
+    url(r'^login/$', 'school.views.login', name='login'),
+    url(r'^logout/$', 'school.views.logout', name='logout'),
+    url(r'^vm/new/(?P<template>\d+)/$', 'one.views.vm_new', name='vm_new'),
+    url(r'^vm/show/(?P<iid>\d+)/$', 'one.views.vm_show', name='vm_show'),
+    url(r'^vm/delete/(?P<iid>\d+)/$', 'one.views.vm_delete',
+        name='vm_delete'),
+    url(r'^vm/stop/(?P<iid>\d+)/$', 'one.views.vm_stop', name='vm_stop'),
+    url(r'^vm/resume/(?P<iid>\d+)/$', 'one.views.vm_resume',
+        name='vm_resume'),
+    url(r'^vm/power_off/(?P<iid>\d+)/$', 'one.views.vm_power_off',
+        name='vm_power_off'),
+    url(r'^vm/restart/(?P<iid>\d+)/$', 'one.views.vm_restart',
+        name='vm_restart'),
+    url(r'^vm/port_add/(?P<iid>\d+)/$', 'one.views.vm_port_add',
+        name='vm_port_add'),
+    url(r'^vm/port_del/(?P<iid>\d+)/(?P<proto>tcp|udp)/(?P<public>\d+)/$',
+        'one.views.vm_port_del', name='vm_port_del'),
+    url(r'^reload/$', 'firewall.views.reload_firewall',
+        name='reload_firewall'),
+    url(r'^fwapi/$', 'firewall.views.firewall_api', name='firewall_api'),
+    url(r'^store/$', 'store.views.index', name='store_index'),
+    url(r'^store/top/$', 'store.views.toplist', name='store_top'),
 )
diff --git a/firewall/admin.py b/firewall/admin.py
index c767457..c7d84b2 100644
--- a/firewall/admin.py
+++ b/firewall/admin.py
@@ -7,7 +7,9 @@ class AliasInline(contrib.admin.TabularInline):
     model = Alias
 
 class HostAdmin(admin.ModelAdmin):
-    list_display = ('hostname', 'vlan', 'ipv4', 'ipv6', 'pub_ipv4', 'mac', 'shared_ip', 'owner', 'groups_l', 'rules_l', 'description', 'reverse')
+    list_display = ('hostname', 'vlan', 'ipv4', 'ipv6', 'pub_ipv4', 'mac',
+        'shared_ip', 'owner', 'groups_l', 'rules_l', 'description',
+        'reverse')
     ordering = ('hostname', )
     list_filter = ('owner', 'vlan', 'groups')
     search_fields = ('hostname', 'description', 'ipv4', 'ipv6', 'mac')
@@ -16,16 +18,21 @@ class HostAdmin(admin.ModelAdmin):
 
 class HostInline(contrib.admin.TabularInline):
     model = Host
-    fields = ('hostname', 'ipv4', 'ipv6', 'pub_ipv4', 'mac', 'shared_ip', 'owner', 'reverse')
+    fields = ('hostname', 'ipv4', 'ipv6', 'pub_ipv4', 'mac', 'shared_ip',
+        'owner', 'reverse')
 
 class VlanAdmin(admin.ModelAdmin):
-    list_display = ('vid', 'name', 'rules_l', 'ipv4', 'net_ipv4', 'ipv6', 'net_ipv6', 'description', 'domain', 'snat_ip', 'snat_to_l')
+    list_display = ('vid', 'name', 'rules_l', 'ipv4', 'net_ipv4', 'ipv6',
+        'net_ipv6', 'description', 'domain', 'snat_ip', 'snat_to_l')
     ordering = ('vid', )
     inlines = (HostInline, )
 
 class RuleAdmin(admin.ModelAdmin):
-    list_display = ('r_type', 'color_desc', 'description', 'vlan_l', 'owner', 'extra', 'direction', 'accept', 'proto', 'sport', 'dport', 'nat', 'nat_dport')
-    list_filter = ('r_type', 'vlan', 'owner', 'direction', 'accept', 'proto', 'nat')
+    list_display = ('r_type', 'color_desc', 'description', 'vlan_l',
+        'owner', 'extra', 'direction', 'accept', 'proto', 'sport', 'dport',
+        'nat', 'nat_dport')
+    list_filter = ('r_type', 'vlan', 'owner', 'direction', 'accept',
+        'proto', 'nat')
 
 class AliasAdmin(admin.ModelAdmin):
     list_display = ('alias', 'host')
diff --git a/firewall/fields.py b/firewall/fields.py
index 904a357..131356d 100644
--- a/firewall/fields.py
+++ b/firewall/fields.py
@@ -25,7 +25,7 @@ class MACAddressField(models.Field):
         super(MACAddressField, self).__init__(*args, **kwargs)
 
     def get_internal_type(self):
-        return "CharField"
+        return 'CharField'
 
     def formfield(self, **kwargs):
         defaults = {'form_class': MACAddressFormField}
@@ -34,13 +34,19 @@ class MACAddressField(models.Field):
 add_introspection_rules([], ["firewall\.fields\.MACAddressField"])
 
 def val_alfanum(value):
-     if not alfanum_re.search(value):
-          raise ValidationError(u'%s - csak betut, kotojelet, alahuzast, szamot tartalmazhat!' % value)
+    if alfanum_re.search(value) is None:
+        raise ValidationError(
+            _(u'%s - only letters, numbers, underscores and hyphens are '
+               'allowed!') % value)
 
 def val_domain(value):
-     if not domain_re.search(value):
-          raise ValidationError(u'%s - helytelen domain' % value)
+    if domain_re.search(value) is None:
+        raise ValidationError(_(u'%s - invalid domain') % value)
 
 def ipv4_2_ipv6(ipv4):
+    """Convert IPv4 addr. string to IPv6 addr. string."""
     m = ipv4_re.match(ipv4)
-    return "2001:738:2001:4031:%s:%s:%s:0" % (m.group(1), m.group(2), m.group(3))
+    if m is None:
+        raise ValidationError(_(u'%s - not an IPv4 address') % ipv4)
+    return ("2001:738:2001:4031:%s:%s:%s:0" %
+        (m.group(1), m.group(2), m.group(3)))