diff --git a/httpclient/src/main/java/org/apache/http/impl/conn/PoolingClientConnectionManager.java b/httpclient/src/main/java/org/apache/http/impl/conn/PoolingClientConnectionManager.java
index 7108d14bd..413f546d4 100644
--- a/httpclient/src/main/java/org/apache/http/impl/conn/PoolingClientConnectionManager.java
+++ b/httpclient/src/main/java/org/apache/http/impl/conn/PoolingClientConnectionManager.java
@@ -96,14 +96,7 @@ public class PoolingClientConnectionManager implements ClientConnectionManager,
     public PoolingClientConnectionManager(
             final SchemeRegistry schemeRegistry,
             final long timeToLive, final TimeUnit tunit) {
-        super();
-        if (schemeRegistry == null) {
-            throw new IllegalArgumentException("Scheme registry may not be null");
-        }
-        this.schemeRegistry = schemeRegistry;
-        this.dnsResolver = new SystemDefaultDnsResolver();
-        this.operator = createConnectionOperator(schemeRegistry);
-        this.pool = new HttpConnPool(this.log, 2, 20, timeToLive, tunit);
+        this(schemeRegistry, timeToLive, tunit, new SystemDefaultDnsResolver());
     }
 
     public PoolingClientConnectionManager(final SchemeRegistry schemeRegistry,
@@ -114,7 +107,7 @@ public class PoolingClientConnectionManager implements ClientConnectionManager,
             throw new IllegalArgumentException("Scheme registry may not be null");
         }
         this.schemeRegistry = schemeRegistry;
-        this.dnsResolver  = new SystemDefaultDnsResolver();
+        this.dnsResolver  = dnsResolver;
         this.operator = createConnectionOperator(schemeRegistry);
         this.pool = new HttpConnPool(this.log, 2, 20, timeToLive, tunit);
     }