diff --git a/astrid/antlib/proguard.jar b/astrid/antlib/proguard.jar
new file mode 100644
index 000000000..56d68ba15
Binary files /dev/null and b/astrid/antlib/proguard.jar differ
diff --git a/astrid/build.xml b/astrid/build.xml
index 88b9f6689..7f6f82379 100644
--- a/astrid/build.xml
+++ b/astrid/build.xml
@@ -61,6 +61,8 @@
 
     <target name="-pre-build" depends="get-version, copy-sources, updatekeys, updatekeys-release, disable-market">
       <mkdir dir="gen" />
+      <property name="proguard.jar" location="antlib/proguard.jar" />
+      <taskdef name="proguard" classname="proguard.ant.ProGuardTask" classpath="${proguard.jar}" />
     </target>
 
     <target name="copy-sources">
diff --git a/astrid/proguard.cfg b/astrid/proguard.cfg
index 94012573f..7788c7d30 100644
--- a/astrid/proguard.cfg
+++ b/astrid/proguard.cfg
@@ -3,7 +3,7 @@
 -dontskipnonpubliclibraryclasses
 -dontpreverify
 -verbose
--optimizations !code/simplification/arithmetic,!field/*,!class/merging/*,!code/allocation/variable,!method/inlining/*
+-optimizations !code/simplification/arithmetic,!field/*,!class/merging/*,!code/allocation/variable,!method/inlining/*,!field/marking/private
 
 # astrid-specific
 -dontobfuscate