diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connection/ConnectionService.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connection/ConnectionService.java
index 27a74207c..f3fb48261 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connection/ConnectionService.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connection/ConnectionService.java
@@ -154,7 +154,7 @@ public class ConnectionService extends ModeledGroupedDirectoryObjectService<Mode
         super.beforeCreate(user, model);
         
         // Name must not be blank
-        if (model.getName().trim().isEmpty())
+        if (model.getName() == null || model.getName().trim().isEmpty())
             throw new GuacamoleClientException("Connection names must not be blank.");
 
         // Do not attempt to create duplicate connections
@@ -171,7 +171,7 @@ public class ConnectionService extends ModeledGroupedDirectoryObjectService<Mode
         super.beforeUpdate(user, model);
         
         // Name must not be blank
-        if (model.getName().trim().isEmpty())
+        if (model.getName() == null || model.getName().trim().isEmpty())
             throw new GuacamoleClientException("Connection names must not be blank.");
         
         // Check whether such a connection is already present
@@ -212,7 +212,7 @@ public class ConnectionService extends ModeledGroupedDirectoryObjectService<Mode
             String value = parameterEntry.getValue();
 
             // There is no need to insert empty parameters
-            if (value.isEmpty())
+            if (value == null || value.isEmpty())
                 continue;
             
             // Produce model object from parameter
diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connectiongroup/ConnectionGroupService.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connectiongroup/ConnectionGroupService.java
index 954b5e0ac..8e7e3a197 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connectiongroup/ConnectionGroupService.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/connectiongroup/ConnectionGroupService.java
@@ -137,7 +137,7 @@ public class ConnectionGroupService extends ModeledGroupedDirectoryObjectService
         super.beforeCreate(user, model);
         
         // Name must not be blank
-        if (model.getName().trim().isEmpty())
+        if (model.getName() == null || model.getName().trim().isEmpty())
             throw new GuacamoleClientException("Connection group names must not be blank.");
         
         // Do not attempt to create duplicate connection groups
@@ -154,7 +154,7 @@ public class ConnectionGroupService extends ModeledGroupedDirectoryObjectService
         super.beforeUpdate(user, model);
         
         // Name must not be blank
-        if (model.getName().trim().isEmpty())
+        if (model.getName() == null || model.getName().trim().isEmpty())
             throw new GuacamoleClientException("Connection group names must not be blank.");
         
         // Check whether such a connection group is already present
diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/user/UserService.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/user/UserService.java
index a84643ed7..6cb7ad36b 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/user/UserService.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/user/UserService.java
@@ -144,7 +144,7 @@ public class UserService extends ModeledDirectoryObjectService<ModeledUser, User
         super.beforeCreate(user, model);
         
         // Username must not be blank
-        if (model.getIdentifier().trim().isEmpty())
+        if (model.getIdentifier() == null || model.getIdentifier().trim().isEmpty())
             throw new GuacamoleClientException("The username must not be blank.");
         
         // Do not create duplicate users
@@ -161,7 +161,7 @@ public class UserService extends ModeledDirectoryObjectService<ModeledUser, User
         super.beforeUpdate(user, model);
         
         // Username must not be blank
-        if (model.getIdentifier().trim().isEmpty())
+        if (model.getIdentifier() == null || model.getIdentifier().trim().isEmpty())
             throw new GuacamoleClientException("The username must not be blank.");
         
         // Check whether such a user is already present