diff --git a/doc/4.1-configuration-syntax.md b/doc/4.1-configuration-syntax.md
index 2c02c9f17..cd96ee8b2 100644
--- a/doc/4.1-configuration-syntax.md
+++ b/doc/4.1-configuration-syntax.md
@@ -20,7 +20,7 @@ define objects the `object` keyword is used:
 
 > **Note**
 >
-> Colons (:) are not permitted in object names.
+> Exclamation marks (!) are not permitted in object names.
 
 Each object is uniquely identified by its type (`Host`) and name
 (`host1.example.org`). Objects can contain a comma-separated list of
diff --git a/lib/config/config_parser.yy b/lib/config/config_parser.yy
index 6d8b9f035..486a80cf6 100644
--- a/lib/config/config_parser.yy
+++ b/lib/config/config_parser.yy
@@ -352,9 +352,9 @@ object_declaration identifier T_STRING object_inherits_specifier expressionlist
 
 		item->SetType($3);
 
-		if (strchr($4, ':') != NULL) {
+		if (strchr($4, '!') != NULL) {
 			std::ostringstream msgbuf;
-			msgbuf << "Name for object '" << $4 << "' of type '" << $3 << "' is invalid: Object names may not contain ':'";
+			msgbuf << "Name for object '" << $4 << "' of type '" << $3 << "' is invalid: Object names may not contain '!'";
 			free($3);
 			BOOST_THROW_EXCEPTION(std::invalid_argument(msgbuf.str()));
 		}
diff --git a/lib/icinga/host.cpp b/lib/icinga/host.cpp
index 2977e31f6..f38eea9c7 100644
--- a/lib/icinga/host.cpp
+++ b/lib/icinga/host.cpp
@@ -152,7 +152,7 @@ void Host::UpdateSlaveServices(void)
 	ObjectLock olock(service_descriptions);
 	BOOST_FOREACH(const Dictionary::Pair& kv, service_descriptions) {
 		std::ostringstream namebuf;
-		namebuf << GetName() << ":" << kv.first;
+		namebuf << GetName() << "!" << kv.first;
 		String name = namebuf.str();
 
 		std::vector<String> path;
diff --git a/lib/icinga/service-downtime.cpp b/lib/icinga/service-downtime.cpp
index 83b45fc43..9596c56a5 100644
--- a/lib/icinga/service-downtime.cpp
+++ b/lib/icinga/service-downtime.cpp
@@ -334,7 +334,7 @@ void Service::UpdateSlaveScheduledDowntimes(void)
 
 	BOOST_FOREACH(const Dictionary::Pair& kv, descs) {
 		std::ostringstream namebuf;
-		namebuf << GetName() << ":" << kv.first;
+		namebuf << GetName() << "!" << kv.first;
 		String name = namebuf.str();
 
 		std::vector<String> path;
diff --git a/lib/icinga/service-notification.cpp b/lib/icinga/service-notification.cpp
index c411b9bb0..ac176fa75 100644
--- a/lib/icinga/service-notification.cpp
+++ b/lib/icinga/service-notification.cpp
@@ -111,7 +111,7 @@ void Service::UpdateSlaveNotifications(void)
 
 	BOOST_FOREACH(const Dictionary::Pair& kv, descs) {
 		std::ostringstream namebuf;
-		namebuf << GetName() << ":" << kv.first;
+		namebuf << GetName() << "!" << kv.first;
 		String name = namebuf.str();
 
 		std::vector<String> path;