diff --git a/common/rdr/ZlibInStream.cxx b/common/rdr/ZlibInStream.cxx
index 6f3a7d0..4053bd1 100644
--- a/common/rdr/ZlibInStream.cxx
+++ b/common/rdr/ZlibInStream.cxx
@@ -16,6 +16,8 @@
  * USA.
  */
 
+#include <assert.h>
+
 #include <rdr/ZlibInStream.h>
 #include <rdr/Exception.h>
 #include <zlib.h>
@@ -26,26 +28,16 @@
 
 ZlibInStream::ZlibInStream(int bufSize_)
   : underlying(0), bufSize(bufSize_ ? bufSize_ : DEFAULT_BUF_SIZE), offset(0),
-    bytesIn(0)
+    zs(NULL), bytesIn(0)
 {
-  zs = new z_stream;
-  zs->zalloc    = Z_NULL;
-  zs->zfree     = Z_NULL;
-  zs->opaque    = Z_NULL;
-  zs->next_in   = Z_NULL;
-  zs->avail_in  = 0;
-  if (inflateInit(zs) != Z_OK) {
-    delete zs;
-    throw Exception("ZlibInStream: inflateInit failed");
-  }
   ptr = end = start = new U8[bufSize];
+  init();
 }
 
 ZlibInStream::~ZlibInStream()
 {
+  deinit();
   delete [] start;
-  inflateEnd(zs);
-  delete zs;
 }
 
 void ZlibInStream::setUnderlying(InStream* is, int bytesIn_)
@@ -60,7 +52,7 @@
   return offset + ptr - start;
 }
 
-void ZlibInStream::reset()
+void ZlibInStream::removeUnderlying()
 {
   ptr = end = start;
   if (!underlying) return;
@@ -72,6 +64,38 @@
   underlying = 0;
 }
 
+void ZlibInStream::reset()
+{
+  deinit();
+  init();
+}
+
+void ZlibInStream::init()
+{
+  assert(zs == NULL);
+
+  zs = new z_stream;
+  zs->zalloc    = Z_NULL;
+  zs->zfree     = Z_NULL;
+  zs->opaque    = Z_NULL;
+  zs->next_in   = Z_NULL;
+  zs->avail_in  = 0;
+  if (inflateInit(zs) != Z_OK) {
+    delete zs;
+    zs = NULL;
+    throw Exception("ZlibInStream: inflateInit failed");
+  }
+}
+
+void ZlibInStream::deinit()
+{
+  assert(zs != NULL);
+  removeUnderlying();
+  inflateEnd(zs);
+  delete zs;
+  zs = NULL;
+}
+
 int ZlibInStream::overrun(int itemSize, int nItems, bool wait)
 {
   if (itemSize > bufSize)
diff --git a/common/rdr/ZlibInStream.h b/common/rdr/ZlibInStream.h
index c26b6d6..6bd4da4 100644
--- a/common/rdr/ZlibInStream.h
+++ b/common/rdr/ZlibInStream.h
@@ -38,11 +38,15 @@
     virtual ~ZlibInStream();
 
     void setUnderlying(InStream* is, int bytesIn);
-    void reset();
+    void removeUnderlying();
     int pos();
+    void reset();
 
   private:
 
+    void init();
+    void deinit();
+
     int overrun(int itemSize, int nItems, bool wait);
     bool decompress(bool wait);
 
diff --git a/common/rfb/TightDecoder.cxx b/common/rfb/TightDecoder.cxx
index cab49fd..1bfa7a9 100644
--- a/common/rfb/TightDecoder.cxx
+++ b/common/rfb/TightDecoder.cxx
@@ -165,7 +165,7 @@
   bufptr += 1;
   buflen -= 1;
 
-  // Flush zlib streams if we are told by the server to do so.
+  // Reset zlib streams if we are told by the server to do so.
   for (int i = 0; i < 4; i++) {
     if (comp_ctl & 1) {
       zis[i].reset();
@@ -309,8 +309,8 @@
     netbuf = new rdr::U8[dataSize];
 
     zis[streamId].readBytes(netbuf, dataSize);
-    zis[streamId].reset();
 
+    zis[streamId].removeUnderlying();
     delete ms;
 
     bufptr = netbuf;
diff --git a/common/rfb/zrleDecode.h b/common/rfb/zrleDecode.h
index 2566171..07d6795 100644
--- a/common/rfb/zrleDecode.h
+++ b/common/rfb/zrleDecode.h
@@ -177,7 +177,7 @@
     }
   }
 
-  zis->reset();
+  zis->removeUnderlying();
 }
 
 #undef ZRLE_DECODE