diff --git a/RtAudio.cpp b/RtAudio.cpp
index cd427f3..8d47585 100644
--- a/RtAudio.cpp
+++ b/RtAudio.cpp
@@ -38,7 +38,7 @@
 */
 /************************************************************************/
 
-// RtAudio: Version 4.0.5
+// RtAudio: Version 4.0.6
 
 #include "RtAudio.h"
 #include <iostream>
@@ -403,7 +403,9 @@ unsigned int RtApi :: getStreamSampleRate( void )
 // implementation.
 struct CoreHandle {
   AudioDeviceID id[2];    // device ids
+#if defined( MAC_OS_X_VERSION_10_5 ) && ( MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_5 )
   AudioDeviceIOProcID procId[2];
+#endif
   UInt32 iStream[2];      // device stream index (or first if using multiple)
   UInt32 nStreams[2];     // number of streams to use
   bool xrun[2];
@@ -5646,7 +5648,7 @@ bool RtApiAlsa :: probeDeviceOpen( unsigned int device, StreamMode mode, unsigne
   }
 
   // Set the buffer number, which in ALSA is referred to as the "period".
-  int totalSize, dir;
+  int totalSize, dir = 0;
   unsigned int periods = 0;
   if ( options ) periods = options->numberOfBuffers;
   totalSize = *bufferSize * periods;
diff --git a/RtAudio.h b/RtAudio.h
index 5c5fd6f..b9bab05 100644
--- a/RtAudio.h
+++ b/RtAudio.h
@@ -42,7 +42,7 @@
   \file RtAudio.h
  */
 
-// RtAudio: Version 4.0.5
+// RtAudio: Version 4.0.6
 
 #ifndef __RTAUDIO_H
 #define __RTAUDIO_H
diff --git a/configure.ac b/configure.ac
index 97989d2..1303437 100644
--- a/configure.ac
+++ b/configure.ac
@@ -8,7 +8,7 @@ AC_CONFIG_FILES([rtaudio-config Makefile tests/Makefile])
 AC_SUBST( GXX, ["no"] )
 
 # Checks for programs.
-AC_PROG_CXX
+AC_PROG_CXX(g++ CC c++ cxx)
 AC_PROG_RANLIB
 AC_PATH_PROG(AR, ar, no)
 if [[ $AR = "no" ]] ; then
diff --git a/doc/doxygen/Doxyfile b/doc/doxygen/Doxyfile
index 74ae894..0888b32 100644
--- a/doc/doxygen/Doxyfile
+++ b/doc/doxygen/Doxyfile
@@ -5,7 +5,7 @@
 #---------------------------------------------------------------------------
 DOXYFILE_ENCODING      = UTF-8
 PROJECT_NAME           = RtAudio
-PROJECT_NUMBER         = 4.0.5
+PROJECT_NUMBER         = 4.0.6
 OUTPUT_DIRECTORY       = .
 CREATE_SUBDIRS         = NO
 OUTPUT_LANGUAGE        = English
diff --git a/doc/doxygen/tutorial.txt b/doc/doxygen/tutorial.txt
index 7f7d5ae..a8dfd25 100644
--- a/doc/doxygen/tutorial.txt
+++ b/doc/doxygen/tutorial.txt
@@ -32,7 +32,7 @@ Devices are now re-enumerated every time the RtAudio::getDeviceCount(), RtAudio:
 
 \section download Download
 
-Latest Release (2 February 2009): <A href="http://www.music.mcgill.ca/~gary/rtaudio/release/rtaudio-4.0.5.tar.gz">Version 4.0.5</A>
+Latest Release (3 June 2009): <A href="http://www.music.mcgill.ca/~gary/rtaudio/release/rtaudio-4.0.6.tar.gz">Version 4.0.6</A>
 
 \section documentation Documentation Links
 
diff --git a/doc/release.txt b/doc/release.txt
index d42b768..313dacd 100644
--- a/doc/release.txt
+++ b/doc/release.txt
@@ -2,6 +2,10 @@ RtAudio - a set of C++ classes that provide a common API for realtime audio inpu
 
 By Gary P. Scavone, 2001-2009.
 
+v4.0.6: (3 June 2009)
+- bug fix in ALSA code to set period size to power of two (thanks to Joakim Karrstrom)
+- bug fix in OS-X for OS < 10.5 ... need preprocessor definition around new variable type (thanks to Tristan Matthews)
+
 v4.0.5: (2 February 2009)
 - added support in CoreAudio for arbitrary stream channel configurations
 - added getStreamSampleRate() function because the actual sample rate can sometimes vary slightly from the specified one (thanks to Theo Veenker)
diff --git a/tests/record.cpp b/tests/record.cpp
index a56f351..4457f93 100644
--- a/tests/record.cpp
+++ b/tests/record.cpp
@@ -153,9 +153,8 @@ int main( int argc, char *argv[] )
   }
 
   std::cout << "\nRecording for " << time << " seconds ... writing file 'record.raw' (buffer frames = " << bufferFrames << ")." << std::endl;
-  while ( 1 ) {
+  while ( adc.isStreamRunning() ) {
     SLEEP( 100 ); // wake every 100 ms to check if we're done
-    if ( adc.isStreamRunning() == false ) break;
   }
 
   // Now write the entire data to the file.