diff --git a/src/main/antlr3/org/JesusFreke/smali/smaliLexer.g b/src/main/antlr3/org/JesusFreke/smali/smaliLexer.g
index edd15f16..2c0245c6 100644
--- a/src/main/antlr3/org/JesusFreke/smali/smaliLexer.g
+++ b/src/main/antlr3/org/JesusFreke/smali/smaliLexer.g
@@ -178,23 +178,13 @@ import java.util.ArrayDeque;
 		tokens.add(token);
 	}
 	
-/*protected void mismatch(IntStream input, int ttype, BitSet follow) throws RecognitionException
-{
-	throw new MismatchedTokenException(ttype, input);
+	public void reportError(RecognitionException e)
+	{
+		throw new RuntimeException(e);
+	}
 }
 
-public Object recoverFromMismatchedSet(IntStream input, RecognitionException e, BitSet follow) throws RecognitionException
-{
-	throw e;
-}*/
 
-}
-
-/*@rulecatch {
-catch (RecognitionException e) {
-throw e;
-}
-}*/
 
 CLASS_PHRASE
 	:	CLASS_DIRECTIVE_EMIT
@@ -207,6 +197,16 @@ SUPER_PHRASE
 		WS
 		CLASS_DESCRIPTOR_EMIT;
 		
+IMPLEMENTS_PHRASE
+	:	IMPLEMENTS_DIRECTIVE_EMIT
+		WS
+		CLASS_DESCRIPTOR_EMIT;
+		
+SOURCE_PHRASE
+	:	SOURCE_DIRECTIVE_EMIT
+		WS
+		STRING_LITERAL_EMIT;			
+		
 FIELD_PHRASE
 	:	FIELD_DIRECTIVE_EMIT
 		WS
@@ -461,7 +461,7 @@ CATCH_PHRASE
 		(LABEL_EMIT | OFFSET_EMIT)
 		WS 'to' WS
 		(LABEL_EMIT | OFFSET_EMIT)
-		WS 'using'
+		WS 'using' WS
 		(LABEL_EMIT | OFFSET_EMIT);
 		
 
@@ -485,6 +485,16 @@ fragment SUPER_DIRECTIVE_EMIT
 	:	SUPER_DIRECTIVE {emit($SUPER_DIRECTIVE, SUPER_DIRECTIVE);};
 fragment SUPER_DIRECTIVE
 	:	'.super';
+
+fragment IMPLEMENTS_DIRECTIVE_EMIT
+	:	IMPLEMENTS_DIRECTIVE {emit($IMPLEMENTS_DIRECTIVE, IMPLEMENTS_DIRECTIVE);};
+fragment IMPLEMENTS_DIRECTIVE
+	:	'.implements';
+	
+fragment SOURCE_DIRECTIVE_EMIT
+	:	SOURCE_DIRECTIVE {emit($SOURCE_DIRECTIVE, SOURCE_DIRECTIVE);};
+fragment SOURCE_DIRECTIVE
+	:	'.source';
 	
 fragment FIELD_DIRECTIVE_EMIT
 	:	FIELD_DIRECTIVE {emit($FIELD_DIRECTIVE, FIELD_DIRECTIVE);};
@@ -505,7 +515,7 @@ fragment REGISTERS_DIRECTIVE_EMIT
 	:	REGISTERS_DIRECTIVE {emit($REGISTERS_DIRECTIVE, REGISTERS_DIRECTIVE);};
 fragment REGISTERS_DIRECTIVE
 	:	'.registers';
-	
+
 fragment ARRAY_DATA_DIRECTIVE_EMIT
 	:	ARRAY_DATA_DIRECTIVE {emit($ARRAY_DATA_DIRECTIVE, ARRAY_DATA_DIRECTIVE);};
 fragment ARRAY_DATA_DIRECTIVE
diff --git a/src/main/antlr3/org/JesusFreke/smali/smaliParser.g b/src/main/antlr3/org/JesusFreke/smali/smaliParser.g
index 00c816c6..aaa4329b 100644
--- a/src/main/antlr3/org/JesusFreke/smali/smaliParser.g
+++ b/src/main/antlr3/org/JesusFreke/smali/smaliParser.g
@@ -38,6 +38,8 @@ tokens {
 	//I_* tokens are imaginary tokens used as parent AST nodes
 	I_CLASS_DEF;
 	I_SUPER;
+	I_IMPLEMENTS;
+	I_SOURCE;
 	I_ACCESS_LIST;
 	I_METHODS;
 	I_FIELDS;
@@ -108,21 +110,81 @@ import org.JesusFreke.dexlib.code.Format.*;
 }
 
 
-smali_file:	header methods_and_fields -> ^(I_CLASS_DEF header methods_and_fields);
+@members {
+	public String getErrorMessage(RecognitionException e,
+		String[] tokenNames)
+	{
+		List stack = getRuleInvocationStack(e, this.getClass().getName());
+		String msg = null;
+		if ( e instanceof NoViableAltException ) {
+			NoViableAltException nvae = (NoViableAltException)e;
+			msg = " no viable alt; token="+e.token+
+			" (decision="+nvae.decisionNumber+
+			" state "+nvae.stateNumber+")"+
+			" decision=<<"+nvae.grammarDecisionDescription+">>";
+		}
+		else {
+			msg = super.getErrorMessage(e, tokenNames);
+		}
+		return stack+" "+msg;
+	}
+	
+	public String getTokenErrorDisplay(Token t) {
+		return t.toString();
+	}
+}
 
-header	:	class_spec super_spec;
 
+smali_file
+	scope
+	{
+		boolean hasClassSpec;
+		boolean hasSuperSpec;
+	}
+	:
+	{
+		$smali_file::hasClassSpec = false;
+		$smali_file::hasSuperSpec = false;
+	}
+	( {!$smali_file::hasClassSpec}?=> class_spec {$smali_file::hasClassSpec = true;}
+	|	{!$smali_file::hasSuperSpec}?=> super_spec {$smali_file::hasSuperSpec = true;}
+	|	implements_spec
+	|	source_spec
+	|	method
+	|	field)*
+	{
+		if (!$smali_file::hasClassSpec) {
+			//TODO: throw correct exception type
+			throw new RuntimeException("The file must contain a .class directive");
+		}
+		
+		if (!$smali_file::hasSuperSpec) {
+			//TODO: throw correct exception type
+			throw new RuntimeException("The file must contain a .super directive");
+		}
+	}
+	->	^(I_CLASS_DEF
+			class_spec
+			super_spec
+			implements_spec*
+			source_spec
+			^(I_METHODS method*) ^(I_FIELDS field*));
+		
 class_spec
 	:	CLASS_DIRECTIVE access_list CLASS_DESCRIPTOR -> CLASS_DESCRIPTOR access_list;
 
 super_spec
 	:	SUPER_DIRECTIVE CLASS_DESCRIPTOR -> ^(I_SUPER[$start, "I_SUPER"] CLASS_DESCRIPTOR);
 
+implements_spec
+	:	IMPLEMENTS_DIRECTIVE CLASS_DESCRIPTOR -> ^(I_IMPLEMENTS[$start, "I_IMPLEMENTS"] CLASS_DESCRIPTOR);
+	
+source_spec
+	:	SOURCE_DIRECTIVE STRING_LITERAL -> ^(I_SOURCE[$start, "I_SOURCE"] STRING_LITERAL);
+
 access_list
 	:	ACCESS_SPEC+ -> ^(I_ACCESS_LIST[$start,"I_ACCESS_LIST"] ACCESS_SPEC+);
 
-methods_and_fields
-	:	(method | field)* -> ^(I_METHODS method*) ^(I_FIELDS field*);
 
 field	:	FIELD_DIRECTIVE access_list MEMBER_NAME field_type_descriptor literal?
 		-> ^(I_FIELD[$start, "I_FIELD"] MEMBER_NAME access_list ^(I_FIELD_TYPE field_type_descriptor) ^(I_FIELD_INITIAL_VALUE literal)?);
diff --git a/src/main/antlr3/org/JesusFreke/smali/smaliTreeWalker.g b/src/main/antlr3/org/JesusFreke/smali/smaliTreeWalker.g
index 5ffaa987..d981bf2b 100644
--- a/src/main/antlr3/org/JesusFreke/smali/smaliTreeWalker.g
+++ b/src/main/antlr3/org/JesusFreke/smali/smaliTreeWalker.g
@@ -90,10 +90,10 @@ import org.JesusFreke.dexlib.code.Format.*;
 smali_file returns[ClassDefItem classDefItem]
 	:	^(I_CLASS_DEF header methods fields);
 
-header	:	class_spec super_spec
+header	:	class_spec super_spec implements_list source_spec
 	{
 		classDataItem = new ClassDataItem(dexFile, 0);
-		classDefItem = new ClassDefItem(dexFile, $class_spec.type, $class_spec.accessFlags, $super_spec.type, classDataItem);
+		classDefItem = new ClassDefItem(dexFile, $class_spec.type, $class_spec.accessFlags, $super_spec.type, $implements_list.implementsList, $source_spec.source, classDataItem);
 	};
 
 class_spec returns[TypeIdItem type, int accessFlags]
@@ -108,6 +108,27 @@ super_spec returns[TypeIdItem type]
 	{
 		$type = $class_type_descriptor.type;
 	};
+	
+
+implements_spec returns[TypeIdItem type]
+	:	^(I_IMPLEMENTS class_type_descriptor)
+	{
+		$type = $class_type_descriptor.type;
+	};
+	
+implements_list returns[TypeListItem implementsList]
+@init	{ ArrayList<TypeIdItem> typeList; }
+	:	{typeList = new ArrayList<TypeIdItem>();}
+		(implements_spec {typeList.add($implements_spec.type);} )*
+		{if (typeList.size() > 0) $implementsList = new TypeListItem(dexFile, typeList);
+		else $implementsList = null;};
+		
+source_spec returns[StringIdItem source]
+	:	{$source = null;}
+		^(I_SOURCE string_literal {$source = new StringIdItem(dexFile, $string_literal.value);})
+	|	;
+		
+	
 
 access_list returns [int value]
 	@init
diff --git a/src/main/java/org/JesusFreke/dexlib/ClassDefItem.java b/src/main/java/org/JesusFreke/dexlib/ClassDefItem.java
index 7bb5b2ec..3ef22945 100644
--- a/src/main/java/org/JesusFreke/dexlib/ClassDefItem.java
+++ b/src/main/java/org/JesusFreke/dexlib/ClassDefItem.java
@@ -69,7 +69,7 @@ public class ClassDefItem extends IndexedItem<ClassDefItem> {
         };
     }
 
-    public ClassDefItem(DexFile dexFile, TypeIdItem classType, int accessFlags, TypeIdItem superType, ClassDataItem classDataItem) {
+    public ClassDefItem(DexFile dexFile, TypeIdItem classType, int accessFlags, TypeIdItem superType, TypeListItem implementsList, StringIdItem source, ClassDataItem classDataItem) {
         super(-1);
 
         this.dexFile = dexFile;
@@ -78,8 +78,8 @@ public class ClassDefItem extends IndexedItem<ClassDefItem> {
                 this.classType = new IndexedItemReference<TypeIdItem>(dexFile, classType, new IntegerField()),
                 this.accessFlags = new IntegerField(accessFlags),
                 superclassType = new IndexedItemReference<TypeIdItem>(dexFile, superType, new IntegerField()),
-                classInterfacesList = new OffsettedItemReference<TypeListItem>(dexFile.TypeListsSection, new IntegerField()),
-                sourceFile = new IndexedItemReference<StringIdItem>(dexFile.StringIdsSection, new IntegerField()),
+                classInterfacesList = new OffsettedItemReference<TypeListItem>(dexFile, implementsList, new IntegerField()),
+                sourceFile = new IndexedItemReference<StringIdItem>(dexFile, source, new IntegerField()),
                 classAnnotations = new OffsettedItemReference<AnnotationDirectoryItem>(dexFile.AnnotationDirectoriesSection, new IntegerField()),
                 classData = new OffsettedItemReference<ClassDataItem>(dexFile, classDataItem, new IntegerField()),
                 staticFieldInitialValues = new OffsettedItemReference<EncodedArrayItem>(dexFile.EncodedArraysSection, new IntegerField())
diff --git a/src/test/resources/examples/HelloWorld2.smali b/src/test/resources/examples/HelloWorld2.smali
index 447c552b..efb8ca49 100644
--- a/src/test/resources/examples/HelloWorld2.smali
+++ b/src/test/resources/examples/HelloWorld2.smali
@@ -1,6 +1,31 @@
 .class public Lorg/JesusFreke/HelloWorld2/HelloWorld2;
+
 .super Landroid/app/Activity;
 
+.source "HelloWorld2.smali"
+
+;two random interfaces with only a single method to implement
+.implements Landroid/util/Printer;
+.implements Landroid/accounts/AccountMonitorListener;
+
+
+
+.method public println(Ljava/lang/String;)V
+    .registers 1
+
+    return-void
+.end method
+
+
+
+
+.method public onAccountsUpdated([Ljava/lang/String;)V
+    .registers 1
+
+    return-void
+.end method
+
+
 .field private helloWorld Ljava/lang/String;
 .field private static helloWorldStatic Ljava/lang/String;