diff --git a/android/.classpath b/android/.classpath
index 1772b2eff..4620a5b3e 100644
--- a/android/.classpath
+++ b/android/.classpath
@@ -2,11 +2,11 @@
 <classpath>
 	<classpathentry kind="src" path="gen"/>
 	<classpathentry excluding="**/.svn/**/*" including="l10n/**/*" kind="src" path="core-resources"/>
-	<classpathentry excluding="**/.svn/**/*|net/sf/openrocket/file/CSVExport.java|net/sf/openrocket/file/motor/MotorLoaderHelper.java|net/sf/openrocket/file/rocksim/export/|net/sf/openrocket/gui/|net/sf/openrocket/plugin/|net/sf/openrocket/preset/loader/|net/sf/openrocket/preset/xml/|net/sf/openrocket/startup/ConcurrentComponentPresetDatabaseLoader.java|net/sf/openrocket/startup/ConcurrentLoadingThrustCurveMotorSetDatabase.java|net/sf/openrocket/startup/Startup.java|net/sf/openrocket/startup/Startup2.java|net/sf/openrocket/startup/VersionHelper.java|net/sf/openrocket/utils/|net/sf/openrocket/startup/OSXStartup.java" kind="src" path="core"/>
+	<classpathentry excluding="**/.svn/**/*|net/sf/openrocket/file/CSVExport.java|net/sf/openrocket/file/motor/MotorLoaderHelper.java|net/sf/openrocket/file/rocksim/export/|net/sf/openrocket/gui/|net/sf/openrocket/plugin/|net/sf/openrocket/preset/loader/|net/sf/openrocket/preset/xml/|net/sf/openrocket/startup/ConcurrentComponentPresetDatabaseLoader.java|net/sf/openrocket/startup/ConcurrentLoadingThrustCurveMotorSetDatabase.java|net/sf/openrocket/startup/OSXStartup.java|net/sf/openrocket/startup/Startup.java|net/sf/openrocket/startup/Startup2.java|net/sf/openrocket/startup/VersionHelper.java|net/sf/openrocket/util/ExpressionParser.java|net/sf/openrocket/utils/" kind="src" path="core"/>
 	<classpathentry kind="src" path="src"/>
 	<classpathentry kind="con" path="com.android.ide.eclipse.adt.ANDROID_FRAMEWORK"/>
 	<classpathentry kind="con" path="com.android.ide.eclipse.adt.LIBRARIES"/>
 	<classpathentry kind="lib" path="libs/android-support-v4.jar"/>
-	<classpathentry kind="lib" path="/OpenRocket/lib/exp4j-0.2.9.jar"/>
+	<classpathentry kind="lib" path="libs/exp4j-rdg.jar"/>
 	<classpathentry kind="output" path="bin/classes"/>
 </classpath>
diff --git a/android/libs/exp4j-rdg.jar b/android/libs/exp4j-rdg.jar
new file mode 100644
index 000000000..8a980164b
Binary files /dev/null and b/android/libs/exp4j-rdg.jar differ
diff --git a/android/src/net/sf/openrocket/android/simservice/SimulationService.java b/android/src/net/sf/openrocket/android/simservice/SimulationService.java
index d241cb68a..9a1dd4911 100644
--- a/android/src/net/sf/openrocket/android/simservice/SimulationService.java
+++ b/android/src/net/sf/openrocket/android/simservice/SimulationService.java
@@ -1,10 +1,15 @@
 package net.sf.openrocket.android.simservice;
 
+import java.util.List;
+
 import net.sf.openrocket.R;
 import net.sf.openrocket.android.CurrentRocketHolder;
 import net.sf.openrocket.android.util.AndroidLogWrapper;
 import net.sf.openrocket.document.Simulation;
+import net.sf.openrocket.simulation.customexpression.CustomExpression;
+import net.sf.openrocket.simulation.customexpression.CustomExpressionSimulationListener;
 import net.sf.openrocket.simulation.exception.SimulationException;
+import net.sf.openrocket.simulation.listeners.SimulationListener;
 import android.app.IntentService;
 import android.app.Notification;
 import android.app.PendingIntent;
@@ -39,8 +44,12 @@ public class SimulationService extends IntentService {
 		SimulationTask t = (SimulationTask) intent.getSerializableExtra("net.sf.openrocket.simulationtask");
 		try {
 			Simulation sim = CurrentRocketHolder.getCurrentRocket().getRocketDocument().getSimulation(t.simulationId);
+
+			List<CustomExpression> exprs = CurrentRocketHolder.getCurrentRocket().getRocketDocument().getCustomExpressions();
+			SimulationListener exprListener = new CustomExpressionSimulationListener(exprs);
+
 			AndroidLogWrapper.d(SimulationService.class, "simulating " + t.simulationId );
-			sim.simulate();
+			sim.simulate(exprListener);
 			CurrentRocketHolder.getCurrentRocket().unlockSimulation(this, t.simulationId);
 		}
 		catch (SimulationException simex) {