Revert "Bug 499717 - Update to Ant 1.10.1"

This reverts commit 749b0fc213a7240ad67df324eccc1e6e7159d0ac.
diff --git a/eclipse.platform.releng.prereqs.sdk/eclipse-sdk-prereqs.target b/eclipse.platform.releng.prereqs.sdk/eclipse-sdk-prereqs.target
index 22f17d1..acd7a38 100644
--- a/eclipse.platform.releng.prereqs.sdk/eclipse-sdk-prereqs.target
+++ b/eclipse.platform.releng.prereqs.sdk/eclipse-sdk-prereqs.target
@@ -25,8 +25,8 @@
       <unit id="javax.servlet.jsp" version="2.2.0.v201112011158"/>
       <unit id="javax.servlet.jsp.source" version="2.2.0.v201112011158"/>
       <unit id="javax.xml" version="1.3.4.v201005080400"/>
-      <unit id="org.apache.ant" version="1.10.1.v20170407-1341"/>  
-      <unit id="org.apache.ant.source" version="1.10.1.v20170407-1341"/>      
+      <unit id="org.apache.ant" version="1.9.6.v201510161327"/>  
+      <unit id="org.apache.ant.source" version="1.9.6.v201510161327"/>      
       <unit id="org.apache.batik.css" version="1.8.0.v20170214-1941"/>
       <unit id="org.apache.batik.util" version="1.8.0.v20170214-1941"/>
       <unit id="org.apache.batik.util.gui" version="1.8.0.v20170214-1941"/>