diff --git a/build/build.xml b/build/build.xml
index 1e5f0259b..d6e00e2bd 100644
--- a/build/build.xml
+++ b/build/build.xml
@@ -1,17 +1,23 @@
 <?xml version="1.0"?>
 <project name="Arduino" default="build">
+  <!--echo message="os.name = ${os.name}" /-->
+  <!--echo message="os.arch = ${os.arch}" /-->
+  <!--echo message="os.version = ${os.version}" /-->
   
   <!-- Sets properties for macosx/windows/linux depending on current system -->
   <condition property="macosx"><os family="mac" /></condition>
   <condition property="windows"><os family="windows" /></condition>
   <condition property="linux"><os family="unix" /></condition>
+  <condition property="linux64"><os family="unix" arch="amd64" /></condition>
   
   <condition property="platform" 
 	     value="macosx"><os family="mac" /></condition>
   <condition property="platform" 
 	     value="windows"><os family="windows" /></condition>
   <condition property="platform" 
-	     value="linux"><os family="unix" /></condition>
+	     value="linux"><os family="unix" arch="i386" /></condition>
+  <condition property="platform" 
+	     value="linux64"><os family="unix" arch="amd64" /></condition>
 
   <!-- Libraries required for running arduino -->
   <fileset dir=".." id="runtime.jars">
@@ -317,13 +323,23 @@
     <copy todir="linux/work" file="linux/dist/arduino" />
     <chmod perm="755" file="linux/work/arduino" />
   </target>
+
+  <target name="linux64-build" depends="linux-build" description="Build linux (64-bit) version">
+    <copy tofile="linux/work/hardware/tools/avrdude" file="linux/dist/tools/avrdude64" overwrite="true" />
+    <copy tofile="linux/work/lib/librxtxSerial.so" file="linux/dist/lib/librxtxSerial64.so" overwrite="true" />
+  </target>
   
   <target name="linux-run" depends="linux-build" 
-	  description="Run Linux version">
+	  description="Run Linux (32-bit) version">
     <exec executable="./linux/work/arduino" spawn="false"/>
   </target>
   
-  <target name="linux-dist" depends="linux-build" 
+  <target name="linux64-run" depends="linux64-build" 
+	  description="Run Linux (64-bit) version">
+    <exec executable="./linux/work/arduino" spawn="false"/>
+  </target>
+
+  <target name="linux-dist" depends="build" 
 	  description="Build .tar.gz of linux version">
 
     <!--get src="http://dev.processing.org/build/jre-tools-6u18-linux-i586.tgz" 
@@ -358,7 +374,10 @@
       =======================================================
     </echo>
   </target>
+
   
+  <target name="linux64-dist" depends="linux-dist" 
+	  description="Build .tar.gz of linux version" />
   
   <!-- - - - - - - - -->
   <!-- Windows       -->
diff --git a/build/linux/dist/lib/librxtxSerial64.so b/build/linux/dist/lib/librxtxSerial64.so
new file mode 100755
index 000000000..853b87a22
Binary files /dev/null and b/build/linux/dist/lib/librxtxSerial64.so differ
diff --git a/build/linux/dist/tools/avrdude64 b/build/linux/dist/tools/avrdude64
new file mode 100755
index 000000000..f13912adc
Binary files /dev/null and b/build/linux/dist/tools/avrdude64 differ
diff --git a/build/shared/examples/4.Communication/MIDI/Midi.pde b/build/shared/examples/4.Communication/MIDI/Midi.pde
index 7a25c852c..3d34a18cc 100644
--- a/build/shared/examples/4.Communication/MIDI/Midi.pde
+++ b/build/shared/examples/4.Communication/MIDI/Midi.pde
@@ -29,7 +29,7 @@ void setup() {
 
 void loop() {
   // play notes from F#-0 (0x1E) to F#-5 (0x5A):
-  for (intnote = 0x1E; note < 0x5A; note ++) {
+  for (int note = 0x1E; note < 0x5A; note ++) {
     //Note on channel 1 (0x90), some note value (note), middle velocity (0x45):
     noteOn(0x90, note, 0x45);
     delay(100);
diff --git a/libraries/Wire/utility/twi.c b/libraries/Wire/utility/twi.c
index 236878c4a..9d7280743 100644
--- a/libraries/Wire/utility/twi.c
+++ b/libraries/Wire/utility/twi.c
@@ -79,7 +79,7 @@ void twi_init(void)
   // initialize twi prescaler and bit rate
   cbi(TWSR, TWPS0);
   cbi(TWSR, TWPS1);
-  TWBR = ((CPU_FREQ / TWI_FREQ) - 16) / 2;
+  TWBR = ((F_CPU / TWI_FREQ) - 16) / 2;
 
   /* twi bit rate formula from atmega128 manual pg 204
   SCL Frequency = CPU Clock Frequency / (16 + (2 * TWBR))
diff --git a/libraries/Wire/utility/twi.h b/libraries/Wire/utility/twi.h
index 1258d8d38..71471c6ae 100755
--- a/libraries/Wire/utility/twi.h
+++ b/libraries/Wire/utility/twi.h
@@ -24,10 +24,6 @@
 
   //#define ATMEGA8
 
-  #ifndef CPU_FREQ
-  #define CPU_FREQ 16000000L
-  #endif
-
   #ifndef TWI_FREQ
   #define TWI_FREQ 100000L
   #endif