diff --git a/pom.xml b/pom.xml
index cbd779e5..244e9bce 100644
--- a/pom.xml
+++ b/pom.xml
@@ -25,11 +25,11 @@
     
     <properties>
         <main.java.package>com.cloudhopper.smpp</main.java.package>
-        <ch-commons-util.version>6.0.2</ch-commons-util.version>
+        <ch-commons-util.version>6.0.3</ch-commons-util.version>
         <ch-commons-charset.version>3.0.2</ch-commons-charset.version>
         <ch-commons-gsm.version>3.0.0</ch-commons-gsm.version>
         <netty.version>3.9.6.Final</netty.version>
-        <slf4j.version>1.7.13</slf4j.version>
+        <slf4j.version>1.7.23</slf4j.version>
     </properties>
 
     <dependencies>
@@ -72,7 +72,7 @@
         <dependency>
             <groupId>ch.qos.logback</groupId>
             <artifactId>logback-classic</artifactId>
-            <version>1.1.3</version>
+            <version>1.2.1</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/src/main/java/com/cloudhopper/smpp/pdu/BaseBind.java b/src/main/java/com/cloudhopper/smpp/pdu/BaseBind.java
index c814b4b7..71b47747 100644
--- a/src/main/java/com/cloudhopper/smpp/pdu/BaseBind.java
+++ b/src/main/java/com/cloudhopper/smpp/pdu/BaseBind.java
@@ -125,7 +125,7 @@ public void appendBodyToString(StringBuilder buffer) {
         buffer.append("systemId [");
         buffer.append(StringUtil.toStringWithNullAsEmpty(this.systemId));
         buffer.append("] password [");
-        buffer.append(StringUtil.toStringWithNullAsEmpty(this.password));
+        buffer.append(StringUtil.toStringWithNullAsEmpty(this.password!=null?(this.password.length()>4?this.password.substring(0,1)+"**"+this.password.substring(this.password.length()-2, this.password.length()-1):this.password):null));
         buffer.append("] systemType [");
         buffer.append(StringUtil.toStringWithNullAsEmpty(this.systemType));
         buffer.append("] interfaceVersion [0x");