diff --git a/src/main/java/com/alibaba/druid/pool/DruidDataSource.java b/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
index 9bdd63cb4a..52bd686bad 100644
--- a/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
+++ b/src/main/java/com/alibaba/druid/pool/DruidDataSource.java
@@ -945,7 +945,9 @@ public class DruidDataSource extends DruidAbstractDataSource
             this.validConnectionChecker = new MySqlValidConnectionChecker();
         } else if (realDriverClassName.equals(JdbcConstants.ORACLE_DRIVER)) {
             this.validConnectionChecker = new OracleValidConnectionChecker();
-        } else if (realDriverClassName.equals(JdbcConstants.SQL_SERVER_DRIVER)) {
+        } else if (realDriverClassName.equals(JdbcConstants.SQL_SERVER_DRIVER)
+        		||realDriverClassName.equals(JdbcConstants.SQL_SERVER_DRIVER_SQLJDBC4)
+        		||realDriverClassName.equals(JdbcConstants.SQL_SERVER_DRIVER_JTDS)) {
             this.validConnectionChecker = new MSSQLValidConnectionChecker();
         } else if (realDriverClassName.equals(JdbcConstants.POSTGRESQL_DRIVER)) {
             this.validConnectionChecker = new PGValidConnectionChecker();
diff --git a/src/main/java/com/alibaba/druid/util/JdbcConstants.java b/src/main/java/com/alibaba/druid/util/JdbcConstants.java
index e76e071371..7c1ee0b274 100644
--- a/src/main/java/com/alibaba/druid/util/JdbcConstants.java
+++ b/src/main/java/com/alibaba/druid/util/JdbcConstants.java
@@ -34,6 +34,8 @@ public interface JdbcConstants {
 
     public static final String SQL_SERVER        = "sqlserver";
     public static final String SQL_SERVER_DRIVER = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
+    public static final String SQL_SERVER_DRIVER_SQLJDBC4 = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
+    public static final String SQL_SERVER_DRIVER_JTDS = "net.sourceforge.jtds.jdbc.Driver";
 
     public static final String ORACLE            = "oracle";
     public static final String ORACLE_DRIVER     = "oracle.jdbc.OracleDriver";