diff --git a/pgjdbc/src/main/java/org/postgresql/core/v3/ConnectionFactoryImpl.java b/pgjdbc/src/main/java/org/postgresql/core/v3/ConnectionFactoryImpl.java
index 75a18ef..8f9f4b8 100644
--- a/pgjdbc/src/main/java/org/postgresql/core/v3/ConnectionFactoryImpl.java
+++ b/pgjdbc/src/main/java/org/postgresql/core/v3/ConnectionFactoryImpl.java
@@ -75,21 +75,6 @@ public class ConnectionFactoryImpl extends ConnectionFactory {
   private int protocolVerion = PROTOCOL_VERSION_351;
   private String connectInfo = "";
 
-  /**
-   * Whitelist of supported client_encoding
-   */
-  public static final HashMap<String, String> CLIENT_ENCODING_WHITELIST = new HashMap<>();
-
-  static {
-    CLIENT_ENCODING_WHITELIST.put("UTF8", "UTF8");
-    CLIENT_ENCODING_WHITELIST.put("UTF-8", "UTF-8");
-    CLIENT_ENCODING_WHITELIST.put("GBK", "GBK");
-    CLIENT_ENCODING_WHITELIST.put("GB18030", "GB18030");
-    CLIENT_ENCODING_WHITELIST.put("LATIN1", "LATIN1");
-  }
-//  public static void setStaticClientEncoding(String client) {
-//      this.CLIENT_ENCODING = client;
-//  }
   public void setClientEncoding(String client) {
      this.CLIENT_ENCODING = client;
   }
@@ -179,13 +164,7 @@ public class ConnectionFactoryImpl extends ConnectionFactory {
   public QueryExecutor openConnectionImpl(HostSpec[] hostSpecs, String user, String database,
                                           Properties info) throws SQLException {
     if (info.getProperty("characterEncoding") != null) {
-      if (CLIENT_ENCODING_WHITELIST.containsKey((info.getProperty("characterEncoding")).toUpperCase(Locale.ENGLISH))) {
-        setClientEncoding(info.getProperty("characterEncoding").toUpperCase(Locale.ENGLISH));
-      } else {
-        LOGGER.warn("unsupported client_encoding: " + info.getProperty(
-                "characterEncoding") + ", to ensure correct operation, please use the specified range " +
-                "of client_encoding.");
-      }
+      setClientEncoding(info.getProperty("characterEncoding").toUpperCase(Locale.ENGLISH));
     }
 
     if (info.getProperty("use_boolean") != null) {
diff --git a/pgjdbc/src/test/java/org/postgresql/test/jdbc4/EncodingTest.java b/pgjdbc/src/test/java/org/postgresql/test/jdbc4/EncodingTest.java
new file mode 100644
index 0000000..404ef6f
--- /dev/null
+++ b/pgjdbc/src/test/java/org/postgresql/test/jdbc4/EncodingTest.java
@@ -0,0 +1,76 @@
+package org.postgresql.test.jdbc4;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.postgresql.test.TestUtil;
+
+import java.sql.*;
+import java.util.Properties;
+
+import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+
+public class EncodingTest {
+
+    private Connection con;
+
+    @After
+    public void tearDown() throws Exception {
+        TestUtil.closeDB(con);
+    }
+
+    /*
+     * Tests encoding change
+     */
+    @Test
+    public void testEncodingChange() throws Exception {
+        Properties properties = new Properties();
+        properties.put("characterEncoding", "SQL_ASCII");
+        con = TestUtil.openDB(properties);
+
+        Statement stmt = con.createStatement();
+        ResultSet rs = stmt.executeQuery("show client_encoding");
+
+        assertTrue(rs.next());
+        String e = rs.getString(1);
+        assertNotNull(e);
+        assertEquals("SQL_ASCII", e);
+
+        TestUtil.createTable(con, "test_encode", "id varchar");
+        String str = "abcde1234l&&&&&7$$";
+        PreparedStatement pstmt = con.prepareStatement("INSERT INTO test_encode VALUES (?);");
+        pstmt.setObject(1, str, Types.VARCHAR);
+        pstmt.executeUpdate();
+        ResultSet rsv = stmt.executeQuery("SELECT id FROM test_encode;");
+        assertTrue(rsv.next());
+        String s = rsv.getString(1);
+        assertNotNull(s);
+        assertEquals(str, s);
+        TestUtil.dropTable(con, "test_encode");
+
+        Properties properties2 = new Properties();
+        properties2.put("characterEncoding", "GBK");
+        con = TestUtil.openDB(properties2);
+
+        Statement stmt2 = con.createStatement();
+        ResultSet rs2 = stmt2.executeQuery("show client_encoding");
+
+        assertTrue(rs2.next());
+        String e2 = rs2.getString(1);
+        assertNotNull(e2);
+        assertEquals("GBK", e2);
+
+        Properties properties3 = new Properties();
+        properties3.put("characterEncoding", "LATIN2");
+        con = TestUtil.openDB(properties3);
+
+        Statement stmt3 = con.createStatement();
+        ResultSet rs3 = stmt3.executeQuery("show client_encoding");
+
+        assertTrue(rs3.next());
+        String e3 = rs3.getString(1);
+        assertNotNull(e3);
+        assertEquals("LATIN2", e3);
+    }
+}