diff --git a/OpenEXR/IlmImf/ImfFastHuf.cpp b/OpenEXR/IlmImf/ImfFastHuf.cpp
index 86c84dce21..82708df0a3 100644
--- a/OpenEXR/IlmImf/ImfFastHuf.cpp
+++ b/OpenEXR/IlmImf/ImfFastHuf.cpp
@@ -129,7 +129,7 @@ FastHufDecoder::FastHufDecoder
     {
         if (currByte - table > numBytes)
         {
-            throw Iex::InputExc ("Error decoding Huffman table "
+            throw IEX_NAMESPACE::InputExc ("Error decoding Huffman table "
                                  "(Truncated table data).");
         }
 
@@ -146,7 +146,7 @@ FastHufDecoder::FastHufDecoder
         {
             if (currByte - table > numBytes)
             {
-                throw Iex::InputExc ("Error decoding Huffman table "
+                throw IEX_NAMESPACE::InputExc ("Error decoding Huffman table "
                                      "(Truncated table data).");
             }
 
@@ -155,7 +155,7 @@ FastHufDecoder::FastHufDecoder
 
             if (symbol + runLen > maxSymbol + 1)
             {
-                throw Iex::InputExc ("Error decoding Huffman table "
+                throw IEX_NAMESPACE::InputExc ("Error decoding Huffman table "
                                      "(Run beyond end of table).");
             }
             
@@ -168,7 +168,7 @@ FastHufDecoder::FastHufDecoder
 
             if (symbol + runLen > maxSymbol + 1)
             {
-                throw Iex::InputExc ("Error decoding Huffman table "
+                throw IEX_NAMESPACE::InputExc ("Error decoding Huffman table "
                                      "(Run beyond end of table).");
             }
 
@@ -256,7 +256,7 @@ FastHufDecoder::FastHufDecoder
         int symbol  = *i >> 6;
 
         if (mapping[codeLen] >= _numSymbols)
-            throw Iex::InputExc ("Huffman decode error "
+            throw IEX_NAMESPACE::InputExc ("Huffman decode error "
                                   "(Invalid symbol in header).");
         
         _idToSymbol[mapping[codeLen]] = symbol;
@@ -401,7 +401,7 @@ FastHufDecoder::buildTables (Int64 *base, Int64 *offset)
                 }
                 else
                 {
-                    throw Iex::InputExc ("Huffman decode error "
+                    throw IEX_NAMESPACE::InputExc ("Huffman decode error "
                                           "(Overrun).");
                 }
                 break;
@@ -578,7 +578,7 @@ FastHufDecoder::decode
      int numDstElems)
 {
     if (numSrcBits < 128)
-        throw Iex::InputExc ("Error choosing Huffman decoder implementation "
+        throw IEX_NAMESPACE::InputExc ("Error choosing Huffman decoder implementation "
                              "(insufficient number of bits).");
 
     //
@@ -662,7 +662,7 @@ FastHufDecoder::decode
 
             if (codeLen > _maxCodeLength)
             {
-                throw Iex::InputExc ("Huffman decode error "
+                throw IEX_NAMESPACE::InputExc ("Huffman decode error "
                                      "(Decoded an invalid symbol).");
             }
 
@@ -673,7 +673,7 @@ FastHufDecoder::decode
             }
             else
             {
-                throw Iex::InputExc ("Huffman decode error "
+                throw IEX_NAMESPACE::InputExc ("Huffman decode error "
                                      "(Decoded an invalid symbol).");
             }
         }
@@ -710,19 +710,19 @@ FastHufDecoder::decode
 
             if (dstIdx < 1)
             {
-                throw Iex::InputExc ("Huffman decode error (RLE code "
+                throw IEX_NAMESPACE::InputExc ("Huffman decode error (RLE code "
                                      "with no previous symbol).");
             }
 
             if (dstIdx + rleCount > numDstElems)
             {
-                throw Iex::InputExc ("Huffman decode error (Symbol run "
+                throw IEX_NAMESPACE::InputExc ("Huffman decode error (Symbol run "
                                      "beyond expected output buffer length).");
             }
 
             if (rleCount <= 0) 
             {
-                throw Iex::InputExc("Huffman decode error"
+                throw IEX_NAMESPACE::InputExc("Huffman decode error"
                                     " (Invalid RLE length)");
             }
 
@@ -760,7 +760,7 @@ FastHufDecoder::decode
 
     if (numSrcBits != 0)
     {
-        throw Iex::InputExc ("Huffman decode error (Compressed data remains "
+        throw IEX_NAMESPACE::InputExc ("Huffman decode error (Compressed data remains "
                              "after filling expected output buffer).");
     }
 }
diff --git a/OpenEXR/IlmImf/ImfZip.cpp b/OpenEXR/IlmImf/ImfZip.cpp
index 93d625e146..3a4f871ab4 100644
--- a/OpenEXR/IlmImf/ImfZip.cpp
+++ b/OpenEXR/IlmImf/ImfZip.cpp
@@ -42,14 +42,14 @@
 
 OPENEXR_IMF_INTERNAL_NAMESPACE_SOURCE_ENTER
 
-Imf::Zip::Zip(size_t maxRawSize):
+Zip::Zip(size_t maxRawSize):
     _maxRawSize(maxRawSize),
     _tmpBuffer(0)
 {
     _tmpBuffer = new char[_maxRawSize];
 }
 
-Imf::Zip::Zip(size_t maxScanLineSize, size_t numScanLines):
+Zip::Zip(size_t maxScanLineSize, size_t numScanLines):
     _maxRawSize(0),
     _tmpBuffer(0)
 {
@@ -57,19 +57,19 @@ Imf::Zip::Zip(size_t maxScanLineSize, size_t numScanLines):
     _tmpBuffer  = new char[_maxRawSize];
 }
 
-Imf::Zip::~Zip()
+Zip::~Zip()
 {
     if (_tmpBuffer) delete[] _tmpBuffer;
 }
 
 size_t
-Imf::Zip::maxRawSize()
+Zip::maxRawSize()
 {
     return _maxRawSize;
 }
 
 size_t
-Imf::Zip::maxCompressedSize()
+Zip::maxCompressedSize()
 {
     return uiAdd (uiAdd (_maxRawSize,
                size_t (ceil (_maxRawSize * 0.01))),
@@ -77,7 +77,7 @@ Imf::Zip::maxCompressedSize()
 }
 
 int
-Imf::Zip::compress(const char *raw, int rawSize, char *compressed)
+Zip::compress(const char *raw, int rawSize, char *compressed)
 {
     //
     // Reorder the pixel data.
@@ -129,14 +129,14 @@ Imf::Zip::compress(const char *raw, int rawSize, char *compressed)
     if (Z_OK != ::compress ((Bytef *)compressed, &outSize,
                 (const Bytef *) _tmpBuffer, rawSize))
     {
-        throw Iex::BaseExc ("Data compression (zlib) failed.");
+        throw IEX_NAMESPACE::BaseExc ("Data compression (zlib) failed.");
     }
 
     return outSize;
 }
 
 int
-Imf::Zip::uncompress(const char *compressed, int compressedSize,
+Zip::uncompress(const char *compressed, int compressedSize,
                                             char *raw)
 {
     //
@@ -148,7 +148,7 @@ Imf::Zip::uncompress(const char *compressed, int compressedSize,
     if (Z_OK != ::uncompress ((Bytef *)_tmpBuffer, &outSize,
                      (const Bytef *) compressed, compressedSize))
     {
-        throw Iex::InputExc ("Data decompression (zlib) failed.");
+        throw IEX_NAMESPACE::InputExc ("Data decompression (zlib) failed.");
     }
 
     //
diff --git a/OpenEXR/IlmImf/dwaLookups.cpp b/OpenEXR/IlmImf/dwaLookups.cpp
index 19ec8311c0..8048878c2e 100644
--- a/OpenEXR/IlmImf/dwaLookups.cpp
+++ b/OpenEXR/IlmImf/dwaLookups.cpp
@@ -62,11 +62,11 @@ namespace {
     class LutHeaderWorker
     {
         public:
-            class Runner : public IlmThread::Thread
+            class Runner : public ILMTHREAD_NAMESPACE::Thread
             {
                 public:
                     Runner(LutHeaderWorker &worker, bool output):
-                        IlmThread::Thread(),
+                        ILMTHREAD_NAMESPACE::Thread(),
                         _worker(worker),
                         _output(output)
                     {
@@ -87,7 +87,7 @@ namespace {
                 private:
                     LutHeaderWorker     &_worker;
                     bool                 _output;
-                    IlmThread::Semaphore _semaphore;
+                    ILMTHREAD_NAMESPACE::Semaphore _semaphore;
 
             }; // class LutHeaderWorker::Runner
 
@@ -436,7 +436,7 @@ generateToNonlinear()
 int
 cpuCount()
 {
-    if (!IlmThread::supportsThreads()) return 1;
+    if (!ILMTHREAD_NAMESPACE::supportsThreads()) return 1;
 
     int cpuCount = 1;
 
@@ -492,7 +492,7 @@ generateLutHeader()
         }
     }
 
-    if (IlmThread::supportsThreads()) {
+    if (ILMTHREAD_NAMESPACE::supportsThreads()) {
         std::vector<LutHeaderWorker::Runner*> runners;
         for (size_t i=0; i<workers.size(); ++i) {
             runners.push_back( new LutHeaderWorker::Runner(*workers[i], (i==0)) );
diff --git a/OpenEXR/IlmImfTest/compareDwa.h b/OpenEXR/IlmImfTest/compareDwa.h
index b5f4082e96..360c27ffb6 100644
--- a/OpenEXR/IlmImfTest/compareDwa.h
+++ b/OpenEXR/IlmImfTest/compareDwa.h
@@ -40,8 +40,8 @@
 
 void compareDwa(int width, 
                 int height,
-                const OPENEXR_IMF_NAMESPACE::Array2D<Imf::Rgba> &src,
-                const OPENEXR_IMF_NAMESPACE::Array2D<Imf::Rgba> &test,
+                const OPENEXR_IMF_NAMESPACE::Array2D<OPENEXR_IMF_NAMESPACE::Rgba> &src,
+                const OPENEXR_IMF_NAMESPACE::Array2D<OPENEXR_IMF_NAMESPACE::Rgba> &test,
                 OPENEXR_IMF_NAMESPACE::RgbaChannels channels);
 
 #endif
diff --git a/OpenEXR/IlmImfUtil/ImfDeepImageLevel.cpp b/OpenEXR/IlmImfUtil/ImfDeepImageLevel.cpp
index 79e5b5615c..44a6e45fec 100644
--- a/OpenEXR/IlmImfUtil/ImfDeepImageLevel.cpp
+++ b/OpenEXR/IlmImfUtil/ImfDeepImageLevel.cpp
@@ -137,7 +137,7 @@ DeepImageLevel::initializeSampleLists ()
 
 
 void			
-DeepImageLevel::resize (const Imath::Box2i& dataWindow)
+DeepImageLevel::resize (const IMATH_NAMESPACE::Box2i& dataWindow)
 {
     //
     // Note: if the following code throws an exception, then the image level
diff --git a/OpenEXR/IlmImfUtil/ImfFlatImageLevel.cpp b/OpenEXR/IlmImfUtil/ImfFlatImageLevel.cpp
index dea943dc4c..574c3fd2a0 100644
--- a/OpenEXR/IlmImfUtil/ImfFlatImageLevel.cpp
+++ b/OpenEXR/IlmImfUtil/ImfFlatImageLevel.cpp
@@ -83,7 +83,7 @@ FlatImageLevel::~FlatImageLevel ()
 
 
 void			
-FlatImageLevel::resize (const Imath::Box2i& dataWindow)
+FlatImageLevel::resize (const IMATH_NAMESPACE::Box2i& dataWindow)
 {
     //
     // Note: if the following code throws an exception, then the image level
diff --git a/OpenEXR/IlmImfUtil/ImfImage.cpp b/OpenEXR/IlmImfUtil/ImfImage.cpp
index bf0d64bc32..a057f29047 100644
--- a/OpenEXR/IlmImfUtil/ImfImage.cpp
+++ b/OpenEXR/IlmImfUtil/ImfImage.cpp
@@ -337,7 +337,7 @@ Image::levelHeight (int ly) const
 
 
 void
-Image::resize (const Imath::Box2i &dataWindow)
+Image::resize (const IMATH_NAMESPACE::Box2i &dataWindow)
 {
     resize (dataWindow, _levelMode, _levelRoundingMode);
 }
@@ -345,7 +345,7 @@ Image::resize (const Imath::Box2i &dataWindow)
 
 void
 Image::resize
-    (const Imath::Box2i &dataWindow,
+    (const IMATH_NAMESPACE::Box2i &dataWindow,
      LevelMode levelMode,
      LevelRoundingMode levelRoundingMode)
 {
diff --git a/OpenEXR/IlmImfUtil/ImfImageLevel.cpp b/OpenEXR/IlmImfUtil/ImfImageLevel.cpp
index 0c65818d90..f93fc70ec8 100644
--- a/OpenEXR/IlmImfUtil/ImfImageLevel.cpp
+++ b/OpenEXR/IlmImfUtil/ImfImageLevel.cpp
@@ -70,7 +70,7 @@ ImageLevel::~ImageLevel ()
 
 
 void			
-ImageLevel::resize (const Imath::Box2i& dataWindow)
+ImageLevel::resize (const IMATH_NAMESPACE::Box2i& dataWindow)
 {
     if (dataWindow.max.x < dataWindow.min.x - 1||
         dataWindow.max.y < dataWindow.min.y - 1)