diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/PostgreSQLAuthenticationProviderModule.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/PostgreSQLAuthenticationProviderModule.java
index aa331c2e2..5241e1276 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/PostgreSQLAuthenticationProviderModule.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/PostgreSQLAuthenticationProviderModule.java
@@ -69,7 +69,12 @@ public class PostgreSQLAuthenticationProviderModule implements Module {
         myBatisProperties.setProperty("JDBC.autoCommit", "false");
         myBatisProperties.setProperty("mybatis.pooled.pingEnabled", "true");
         myBatisProperties.setProperty("mybatis.pooled.pingQuery", "SELECT 1");
-        myBatisProperties.setProperty("mybatis.configuration.defaultStatementTimeout", environment.getPostgreSQLDefaultStatementTimeout());
+
+        // Only set if > 0. Underlying backend does not take 0 as not-set.
+        int defaultStatementTimeout = environment.getPostgreSQLDefaultStatementTimeout();
+        if(defaultStatementTimeout > 0) {
+            myBatisProperties.setProperty("mybatis.configuration.defaultStatementTimeout", String.valueOf(defaultStatementTimeout));
+        }
 
         // Use UTF-8 in database
         driverProperties.setProperty("characterEncoding", "UTF-8");
diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLEnvironment.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLEnvironment.java
index d7e4daeee..7ce4795ce 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLEnvironment.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLEnvironment.java
@@ -51,10 +51,10 @@ public class PostgreSQLEnvironment extends JDBCEnvironment {
     /**
      * The default defaultStatementTimeout (in seconds),
      * if POSTGRESQL_DEFAULT_STATEMENT_TIMEOUT is not specified.
-     * Default to null (no timeout)
+     * Default to 0 (no timeout, property won't be set)
      * https://mybatis.org/mybatis-3/configuration.html
      */
-    private static final String DEFAULT_DEFAULT_STATEMENT_TIMEOUT = "null";
+    private static final int DEFAULT_DEFAULT_STATEMENT_TIMEOUT = 0;
 
     /**
      * The default socketTimeout (in seconds), if POSTGRESQL_SOCKET_TIMEOUT is not specified.
@@ -267,7 +267,8 @@ public class PostgreSQLEnvironment extends JDBCEnvironment {
     
     /**
      * Returns the defaultStatementTimeout set for PostgreSQL connections.
-     * If unspecified, this will be the default "null" (no timeout)
+     * If unspecified, this will be the default 0,
+     * and should not be passed through to the backend.
      * 
      * @return
      *     The statement timeout (in seconds)
@@ -275,7 +276,7 @@ public class PostgreSQLEnvironment extends JDBCEnvironment {
      * @throws GuacamoleException 
      *     If an error occurs while retrieving the property value.
      */
-    public String getPostgreSQLDefaultStatementTimeout() throws GuacamoleException {
+    public int getPostgreSQLDefaultStatementTimeout() throws GuacamoleException {
         return getProperty(
             PostgreSQLGuacamoleProperties.POSTGRESQL_DEFAULT_STATEMENT_TIMEOUT,
             DEFAULT_DEFAULT_STATEMENT_TIMEOUT
diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLGuacamoleProperties.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLGuacamoleProperties.java
index 128b5c348..feaf85536 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLGuacamoleProperties.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLGuacamoleProperties.java
@@ -98,8 +98,8 @@ public class PostgreSQLGuacamoleProperties {
      * Sets the number of seconds the driver will wait for
      * a response from the database.
      */
-    public static final StringGuacamoleProperty
-            POSTGRESQL_DEFAULT_STATEMENT_TIMEOUT = new StringGuacamoleProperty(){
+    public static final IntegerGuacamoleProperty
+            POSTGRESQL_DEFAULT_STATEMENT_TIMEOUT = new IntegerGuacamoleProperty(){
 
         @Override
         public String getName() { return "postgresql-default-statement-timeout"; }