diff --git a/Sources/CMakeLists.txt b/Sources/CMakeLists.txt
index 72a25a5..87889fd 100755
--- a/Sources/CMakeLists.txt
+++ b/Sources/CMakeLists.txt
@@ -59,6 +59,8 @@ if(USE_SYSTEM_ZLIB)
     else()
         message(FATAL_ERROR "Error! USE_SYSTEM_ZLIB is set but neccessary developer files are missing")
     endif()
+else()
+    include_directories(${CMAKE_SOURCE_DIR}/Engine/zlib)
 endif()
 
 # RAKE! Where to install the binaries.
diff --git a/Sources/Engine/Base/Unzip.cpp b/Sources/Engine/Base/Unzip.cpp
index 042a30f..a76bb57 100644
--- a/Sources/Engine/Base/Unzip.cpp
+++ b/Sources/Engine/Base/Unzip.cpp
@@ -32,7 +32,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 typedef unsigned char Byte;  // !!! FIXME:  not sure why I suddenly needed this typedef here.
 #endif
 
-#include <Engine/zlib/zlib.h>
+#include <zlib.h>
 extern CTCriticalSection zip_csLock; // critical section for access to zlib functions
 
 #pragma pack(1)
diff --git a/Sources/Engine/Network/Compression.cpp b/Sources/Engine/Network/Compression.cpp
index fe788a3..509744c 100644
--- a/Sources/Engine/Network/Compression.cpp
+++ b/Sources/Engine/Network/Compression.cpp
@@ -18,7 +18,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include <Engine/Base/Stream.h>
 #include <Engine/Network/Compression.h>
 #include <Engine/Base/Synchronization.h>
-#include <Engine/zlib/zlib.h>
+#include <zlib.h>
 
 extern CTCriticalSection zip_csLock; // critical section for access to zlib functions