diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4cb1e49dfb..cd025116ff 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -52,10 +52,10 @@ FIND_LIBRARY(lib_glew GLEW REQUIRED)
 ENABLE_LANGUAGE(ASM-NASM)
 
 SET(CMAKE_CXX_FLAGS "-Wall -Wnon-virtual-dtor -Woverloaded-virtual -pipe -lrt -ldl")
-SET(CMAKE_CXX_FLAGS_DEBUG "-g -O0 -D_GLIBCXX_NO_DEBUG")
-SET(CMAKE_CXX_FLAGS_PROFILE "-g -pg -O2 -DNDEBUG")
-SET(CMAKE_CXX_FLAGS_RELEASE "-O3 -DNDEBUG")
-SET(CMAKE_CXX_FLAGS_DEBIAN "-O2 -DNDEBUG")
+SET(CMAKE_CXX_FLAGS_DEBUG "-g -O0 -D_GLIBCXX_NO_DEBUG -DEXPENSIVE_DEBUG")
+SET(CMAKE_CXX_FLAGS_PROFILE "-g -pg -O2")
+SET(CMAKE_CXX_FLAGS_RELEASE "-O3")
+SET(CMAKE_CXX_FLAGS_DEBIAN "-O2")
 
 ADD_DEFINITIONS(-DDATADIR="${CMAKE_INSTALL_PREFIX}/share/lightspark")
 
diff --git a/abc.cpp b/abc.cpp
index 1fcce45378..c047288553 100644
--- a/abc.cpp
+++ b/abc.cpp
@@ -1293,7 +1293,7 @@ void ABCVm::Run(ABCVm* th)
 		th->FPM=new llvm::FunctionPassManager(th->module);
 	      
 		th->FPM->add(new llvm::TargetData(*th->ex->getTargetData()));
-#ifndef NDEBUG
+#ifdef EXPENSIVE_DEBUG
 		//This is pretty heavy, do not enable in release
 		th->FPM->add(llvm::createVerifierPass());
 #endif
diff --git a/debian/changelog b/debian/changelog
index c870bf139a..d4dcd06325 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+lightspark (0.3.3-ubuntu1) lucid; urgency=low
+
+  * Enable assertions in relese builds
+
+ -- Alessandro Pignotti <a.pignotti@sssup.it>  Wed, 19 May 2010 05:26:49 +0200
+
 lightspark (0.3.2-ubuntu1) lucid; urgency=low
 
   * Enable debug output in release
diff --git a/swftypes.cpp b/swftypes.cpp
index 02e2586d47..5fcff12b95 100644
--- a/swftypes.cpp
+++ b/swftypes.cpp
@@ -750,7 +750,7 @@ void ASObject::check() const
 	//Put here a bunch of safety check on the object
 	assert(ref_count>0);
 	//Heavyweight stuff
-#ifndef NDEBUG
+#ifdef EXPENSIVE_DEBUG
 	variables_map::const_var_iterator it=Variables.Variables.begin();
 	for(;it!=Variables.Variables.end();it++)
 	{