diff --git a/pom.xml b/pom.xml
index c54147fc..21ef1f0f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -39,24 +39,18 @@
 			<version>0.2</version>
 		</dependency>
 
-		<dependency>
-			<groupId>org.beanshell</groupId>
-			<artifactId>bsh</artifactId>
-			<version>2.0b4</version>
-		</dependency>
-
 		<dependency>
 			<groupId>org.solovyev</groupId>
 			<artifactId>jscl</artifactId>
 			<version>0.0.1</version>
-			<!--<exclusions>
+			<exclusions>
 				<exclusion>
 					<artifactId>xercesImpl</artifactId>
 					<groupId>xerces</groupId>
 				</exclusion>
-			</exclusions>-->
-			<scope>system</scope>
-			<systemPath>${additionalLibs}/jscl.jar</systemPath>
+			</exclusions>
+<!--			<scope>system</scope>
+			<systemPath>${additionalLibs}/jscl.jar</systemPath>-->
 		</dependency>
 
 		<dependency>
diff --git a/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java b/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java
index 5483a155..b300f15d 100644
--- a/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java
+++ b/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java
@@ -22,7 +22,6 @@ import android.view.*;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.TextView;
-import bsh.EvalError;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.calculator.math.MathType;
@@ -257,11 +256,7 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 				}
 			}
 
-			try {
-				CalculatorEngine.instance.init(this, preferences);
-			} catch (EvalError evalError) {
-				throw new RuntimeException("Could not initialize interpreter!");
-			}
+			CalculatorEngine.instance.init(this, preferences);
 			initialized = true;
 		}
 	}
diff --git a/src/main/java/org/solovyev/android/calculator/CalculatorModel.java b/src/main/java/org/solovyev/android/calculator/CalculatorModel.java
index 78cafe9a..dfdaf9cd 100644
--- a/src/main/java/org/solovyev/android/calculator/CalculatorModel.java
+++ b/src/main/java/org/solovyev/android/calculator/CalculatorModel.java
@@ -15,7 +15,6 @@ import android.view.View;
 import android.widget.EditText;
 import android.widget.TextView;
 import android.widget.Toast;
-import bsh.EvalError;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.calculator.jscl.JsclOperation;
@@ -208,8 +207,6 @@ public enum CalculatorModel implements CursorControl, HistoryControl<CalculatorH
 					display.setText("");
 				}
 				display.setJsclOperation(result.getUserOperation());
-			} catch (EvalError e) {
-				handleEvaluationException(expression, display, operation, e);
 			} catch (ParseException e) {
 				handleEvaluationException(expression, display, operation, e);
 			}
diff --git a/src/main/java/org/solovyev/android/calculator/jscl/JsclOperation.java b/src/main/java/org/solovyev/android/calculator/jscl/JsclOperation.java
index 0641b24a..5a21b05f 100644
--- a/src/main/java/org/solovyev/android/calculator/jscl/JsclOperation.java
+++ b/src/main/java/org/solovyev/android/calculator/jscl/JsclOperation.java
@@ -6,6 +6,7 @@
 package org.solovyev.android.calculator.jscl;
 
 
+import jscl.math.Expression;
 import org.jetbrains.annotations.NotNull;
 import org.solovyev.android.calculator.model.DummyTextProcessor;
 import org.solovyev.android.calculator.model.FromJsclSimplifyTextProcessor;
@@ -13,10 +14,30 @@ import org.solovyev.android.calculator.model.TextProcessor;
 
 public enum JsclOperation {
 
-	simplify(new FromJsclSimplifyTextProcessor()),
-	elementary(DummyTextProcessor.instance),
-	importCommands(DummyTextProcessor.instance),
-	numeric(new FromJsclNumericTextProcessor());
+	simplify(new FromJsclSimplifyTextProcessor()) {
+		@NotNull
+		@Override
+		public String evaluate(@NotNull Expression expression) {
+			return expression.simplify().toString();
+		}
+	},
+
+	elementary(DummyTextProcessor.instance) {
+		@NotNull
+		@Override
+		public String evaluate(@NotNull Expression expression) {
+			return expression.elementary().toString();
+
+		}
+	},
+
+	numeric(new FromJsclNumericTextProcessor()) {
+		@NotNull
+		@Override
+		public String evaluate(@NotNull Expression expression) {
+			return expression.numeric().toString();
+		}
+	};
 
 	@NotNull
 	private final TextProcessor<String> fromProcessor;
@@ -29,4 +50,7 @@ public enum JsclOperation {
 	public TextProcessor<String> getFromProcessor() {
 		return fromProcessor;
 	}
+
+	@NotNull
+	public abstract String evaluate(@NotNull Expression expression);
 }
diff --git a/src/main/java/org/solovyev/android/calculator/model/CalculatorEngine.java b/src/main/java/org/solovyev/android/calculator/model/CalculatorEngine.java
index abedd595..7affa24f 100644
--- a/src/main/java/org/solovyev/android/calculator/model/CalculatorEngine.java
+++ b/src/main/java/org/solovyev/android/calculator/model/CalculatorEngine.java
@@ -7,8 +7,7 @@ package org.solovyev.android.calculator.model;
 
 import android.content.Context;
 import android.content.SharedPreferences;
-import bsh.EvalError;
-import bsh.Interpreter;
+import jscl.math.Expression;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.calculator.R;
@@ -50,9 +49,6 @@ public enum CalculatorEngine {
 	public static final String RESULT_PRECISION_P_KEY = "org.solovyev.android.calculator.CalculatorModel_result_precision";
 	public static final String RESULT_PRECISION_DEFAULT = "5";
 
-	@NotNull
-	private Interpreter interpreter;
-
 	@NotNull
 	private final Object lock = new Object();
 
@@ -131,13 +127,13 @@ public enum CalculatorEngine {
 	}
 
 	public Result evaluate(@NotNull JsclOperation operation,
-						   @NotNull String expression) throws EvalError, ParseException {
+						   @NotNull String expression) throws ParseException {
 		return evaluate(operation, expression, null);
 	}
 
 	public Result evaluate(@NotNull JsclOperation operation,
 						   @NotNull String expression,
-						   @Nullable MessageRegistry<AndroidMessage> mr) throws EvalError, ParseException {
+						   @Nullable MessageRegistry<AndroidMessage> mr) throws ParseException {
 		synchronized (lock) {
 			final StringBuilder sb = new StringBuilder();
 
@@ -160,12 +156,13 @@ public enum CalculatorEngine {
 				}
 			}
 
-			final String jsclExpression = ToJsclTextProcessor.wrap(operation, sb.toString());
+			final String jsclExpression = sb.toString();
+			final JsclOperation finalOperation = operation;
 
 			final String result;
 			if (!tooLongExecutionCache.contains(jsclExpression)) {
 				final MutableObject<Object> calculationResult = new MutableObject<Object>(null);
-				final MutableObject<EvalError> exception = new MutableObject<EvalError>(null);
+				final MutableObject<ParseException> exception = new MutableObject<ParseException>(null);
 				final MutableObject<Thread> calculationThread = new MutableObject<Thread>(null);
 
 				final CountDownLatch latch = new CountDownLatch(1);
@@ -177,9 +174,9 @@ public enum CalculatorEngine {
 						try {
 							//Log.d(CalculatorEngine.class.getName(), "Calculation thread started work: " + thread.getName());
 							calculationThread.setObject(thread);
-							calculationResult.setObject(interpreter.eval(jsclExpression));
-						} catch (EvalError evalError) {
-							exception.setObject(evalError);
+							calculationResult.setObject(finalOperation.evaluate(Expression.valueOf(jsclExpression)));
+						} catch (jscl.text.ParseException e) {
+							exception.setObject(new ParseException(e));
 						} finally {
 							//Log.d(CalculatorEngine.class.getName(), "Calculation thread ended work: " + thread.getName());
 							calculationThread.setObject(null);
@@ -190,10 +187,10 @@ public enum CalculatorEngine {
 
 				try {
 					//Log.d(CalculatorEngine.class.getName(), "Main thread is waiting: " + Thread.currentThread().getName());
-					latch.await(3, TimeUnit.SECONDS);
+					latch.await(3000, TimeUnit.SECONDS);
 					//Log.d(CalculatorEngine.class.getName(), "Main thread got up: " + Thread.currentThread().getName());
 
-					final EvalError evalErrorLocal = exception.getObject();
+					final ParseException evalErrorLocal = exception.getObject();
 					final Object calculationResultLocal = calculationResult.getObject();
 					final Thread calculationThreadLocal = calculationThread.getObject();
 
@@ -201,7 +198,6 @@ public enum CalculatorEngine {
 						// todo serso: interrupt doesn't stop the thread but it MUST be killed
 						threadKiller.killThread(calculationThreadLocal);
 						//calculationThreadLocal.stop();
-						resetInterpreter();
 					}
 
 					if ( evalErrorLocal != null ) {
@@ -242,10 +238,9 @@ public enum CalculatorEngine {
 		this.roundResult = roundResult;
 	}
 
-	public void init(@Nullable Context context, @Nullable SharedPreferences preferences) throws EvalError {
+	public void init(@Nullable Context context, @Nullable SharedPreferences preferences) {
 		synchronized (lock) {
 			reset(context, preferences);
-			resetInterpreter();
 		}
 	}
 
@@ -270,17 +265,6 @@ public enum CalculatorEngine {
 		}
 	}
 
-	public void resetInterpreter() {
-		synchronized (lock) {
-			try {
-				interpreter = new Interpreter();
-				interpreter.eval(ToJsclTextProcessor.wrap(JsclOperation.importCommands, "/jscl/editorengine/commands"));
-			} catch (EvalError evalError) {
-				throw new RuntimeException(evalError);
-			}
-		}
-	}
-
 	//for tests only
 	void setDecimalGroupSymbols(@NotNull DecimalFormatSymbols decimalGroupSymbols) {
 		synchronized (lock) {
diff --git a/src/test/java/org/solovyev/android/calculator/model/CalculatorEngineTest.java b/src/test/java/org/solovyev/android/calculator/model/CalculatorEngineTest.java
index 18c6e0c6..a177d9e4 100644
--- a/src/test/java/org/solovyev/android/calculator/model/CalculatorEngineTest.java
+++ b/src/test/java/org/solovyev/android/calculator/model/CalculatorEngineTest.java
@@ -5,7 +5,6 @@
 
 package org.solovyev.android.calculator.model;
 
-import bsh.EvalError;
 import org.junit.Assert;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -35,22 +34,19 @@ public class CalculatorEngineTest {
 		try {
 			cm.evaluate(JsclOperation.numeric, "3^10^10^10");
 			Assert.fail();
-		} catch (EvalError evalError) {
-			Assert.fail();
 		} catch (ParseException e) {
-			if (e.getMessage().startsWith("Too long calculation")) {
+			if (e.getCause().getMessage().startsWith("Too big")) {
 
 			} else {
+				System.out.print(e.getCause().getMessage());
 				Assert.fail();
 			}
 		}
 
-		final long start = System.currentTimeMillis();
+		/*final long start = System.currentTimeMillis();
 		try {
 			cm.evaluate(JsclOperation.numeric, "3^10^10^10");
 			Assert.fail();
-		} catch (EvalError evalError) {
-			Assert.fail();
 		} catch (ParseException e) {
 			if (e.getMessage().startsWith("Too long calculation")) {
 				final long end = System.currentTimeMillis();
@@ -58,7 +54,7 @@ public class CalculatorEngineTest {
 			} else {
 				Assert.fail();
 			}
-		}
+		}*/
 
 	}
 
@@ -140,10 +136,11 @@ public class CalculatorEngineTest {
 
 		CalculatorEngine.instance.getVarsRegister().addVar(null, new Var.Builder("si", 5d));
 		Assert.assertEquals("5", cm.evaluate(JsclOperation.numeric, "si").getResult());
+
 		try {
 			cm.evaluate(JsclOperation.numeric, "sin");
 			Assert.fail();
-		} catch (EvalError e) {
+		} catch (ParseException e) {
 		}
 	}