diff --git a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineConfigurer.java b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineConfigurer.java
index 290af6b..16279d1 100644
--- a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineConfigurer.java
+++ b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineConfigurer.java
@@ -23,6 +23,7 @@
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.debug.core.ILaunch;
+import org.eclipse.dltk.launching.IInterpreterInstall;
 import org.eclipse.dltk.launching.InterpreterConfig;
 import org.eclipse.dltk.launching.debug.DbgpConnectionConfig;
 import org.eclipse.koneki.ldt.debug.core.internal.Activator;
@@ -33,11 +34,12 @@
 	private InterpreterConfig initialConfig;
 
 	@Override
-	public InterpreterConfig alterConfig(ILaunch launch, InterpreterConfig config) throws CoreException {
+	public InterpreterConfig alterConfig(final ILaunch launch, final InterpreterConfig config, final IInterpreterInstall interpreterinstall)
+			throws CoreException {
 		// In debug engine the config must not be alter, surely because it is used as key to retreive the DBGPConnectionConfig.
 		initialConfig = config;
 		InterpreterConfig interpreterConfig = (InterpreterConfig) config.clone();
-		return super.alterConfig(launch, interpreterConfig);
+		return super.alterConfig(launch, interpreterConfig, interpreterinstall);
 	}
 
 	protected List<IPath> getLuaPath(ILaunch launch, InterpreterConfig config) throws CoreException {
diff --git a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineRunner.java b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineRunner.java
index 8f34810..aa15e30 100644
--- a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineRunner.java
+++ b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericDebuggingEngineRunner.java
@@ -32,7 +32,7 @@
 	@Override
 	protected InterpreterConfig addEngineConfig(InterpreterConfig config, PreferencesLookupDelegate delegate, ILaunch launch) throws CoreException {
 		LuaGenericDebuggingEngineConfigurer luaGenericDebuggingEngineConfigurer = new LuaGenericDebuggingEngineConfigurer();
-		InterpreterConfig alteredConfig = luaGenericDebuggingEngineConfigurer.alterConfig(launch, config);
+		InterpreterConfig alteredConfig = luaGenericDebuggingEngineConfigurer.alterConfig(launch, config, getInstall());
 		return alteredConfig;
 	}
 
@@ -69,4 +69,15 @@
 		LuaGenericInterpreterCommandLineRenderer commandLineRenderer = new LuaGenericInterpreterCommandLineRenderer();
 		return commandLineRenderer.renderCommandLine(config, getInstall());
 	}
+
+	// TODO HACK ENV_VAR : make environment variable defined at interpreter
+	// level less priority
+	// ****************************************************************************
+	@Override
+	protected String[] getEnvironmentVariablesAsStrings(InterpreterConfig config) {
+		return config.getEnvironmentAsStrings();
+	}
+	// END HACK
+	// ****************************************************************************
+
 }
diff --git a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterConfigurer.java b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterConfigurer.java
index 9754376..4dff1ef 100644
--- a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterConfigurer.java
+++ b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterConfigurer.java
@@ -14,6 +14,7 @@
 import java.util.ArrayList;
 import java.util.EnumSet;
 import java.util.List;
+import java.util.Map;
 
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.ResourcesPlugin;
@@ -22,7 +23,10 @@
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.debug.core.ILaunch;
+import org.eclipse.debug.core.ILaunchManager;
 import org.eclipse.dltk.core.DLTKCore;
+import org.eclipse.dltk.launching.EnvironmentVariable;
+import org.eclipse.dltk.launching.IInterpreterInstall;
 import org.eclipse.dltk.launching.InterpreterConfig;
 import org.eclipse.dltk.launching.ScriptLaunchConfigurationConstants;
 import org.eclipse.koneki.ldt.core.IProjectSourceRootFolderVisitor;
@@ -35,7 +39,25 @@
 	private static final String LUA_INIT_PATTERN = LuaDebugConstants.WILDCARD_PATTERN + File.separator + LuaDebugConstants.LUA_INIT_PATTERN;
 	private static final String LUAC_INIT_PATTERN = LuaDebugConstants.WILDCARD_PATTERN + File.separator + LuaDebugConstants.LUAC_INIT_PATTERN;
 
-	public InterpreterConfig alterConfig(final ILaunch launch, final InterpreterConfig config) throws CoreException {
+	public InterpreterConfig alterConfig(final ILaunch launch, final InterpreterConfig config, final IInterpreterInstall interpreterinstall)
+			throws CoreException {
+
+		// TODO HACK ENV_VAR : make environment variable defined at interpreter level less priority
+		// ****************************************************************************
+		// get launch conf env var
+		@SuppressWarnings("unchecked")
+		final Map<String, String> configEnvs = launch.getLaunchConfiguration().getAttribute(ILaunchManager.ATTR_ENVIRONMENT_VARIABLES,
+				(Map<?, ?>) null);
+		EnvironmentVariable[] interEnvs = interpreterinstall.getEnvironmentVariables();
+		// add var defined at interpreter level only if it was not defined at launch conf level
+		if (interEnvs != null) {
+			for (EnvironmentVariable envVar : interEnvs) {
+				if (configEnvs == null || !configEnvs.containsKey(envVar.getName()))
+					config.addEnvVar(envVar.getName(), envVar.getValue());
+			}
+		}
+		// END HACK
+		// ****************************************************************************
 
 		// Append project path to $LUA_PATH
 		final String envLuaPath = config.getEnvVar(LuaDebugConstants.LUA_PATH);
diff --git a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterRunner.java b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterRunner.java
index f5b2f4f..6b7bfc4 100644
--- a/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterRunner.java
+++ b/plugins/org.eclipse.koneki.ldt.debug.core/src/org/eclipse/koneki/ldt/debug/core/internal/interpreter/generic/LuaGenericInterpreterRunner.java
@@ -28,7 +28,7 @@
 		LuaGenericInterpreterConfigurer luaGenericInterpreterConfigurer = new LuaGenericInterpreterConfigurer();
 
 		try {
-			luaGenericInterpreterConfigurer.alterConfig(launch, config);
+			luaGenericInterpreterConfigurer.alterConfig(launch, config, getInstall());
 		} catch (CoreException e) {
 			// TODO we should be able to raise a core exception here (We should open a DLTK bug ?)
 			Activator.log(e.getStatus());
@@ -40,4 +40,15 @@
 		LuaGenericInterpreterCommandLineRenderer commandLineRenderer = new LuaGenericInterpreterCommandLineRenderer();
 		return commandLineRenderer.renderCommandLine(config, getInstall());
 	}
+
+	// TODO HACK ENV_VAR : make environment variable defined at interpreter
+	// level less priority
+	// ****************************************************************************
+	@Override
+	protected String[] getEnvironmentVariablesAsStrings(InterpreterConfig config) {
+		return config.getEnvironmentAsStrings();
+	}
+	// END HACK
+	// ****************************************************************************
+
 }
diff --git a/plugins/org.eclipse.koneki.ldt.support.lua51/src/org/eclipse/koneki/ldt/support/lua51/internal/interpreter/JNLua51DebuggingEngineRunner.java b/plugins/org.eclipse.koneki.ldt.support.lua51/src/org/eclipse/koneki/ldt/support/lua51/internal/interpreter/JNLua51DebuggingEngineRunner.java
index 8ad226d..2bf8285 100644
--- a/plugins/org.eclipse.koneki.ldt.support.lua51/src/org/eclipse/koneki/ldt/support/lua51/internal/interpreter/JNLua51DebuggingEngineRunner.java
+++ b/plugins/org.eclipse.koneki.ldt.support.lua51/src/org/eclipse/koneki/ldt/support/lua51/internal/interpreter/JNLua51DebuggingEngineRunner.java
@@ -32,7 +32,7 @@
 	@Override
 	protected InterpreterConfig addEngineConfig(InterpreterConfig config, PreferencesLookupDelegate delegate, ILaunch launch) throws CoreException {
 		JNLua51DebuggingEngineConfigurer configurer = new JNLua51DebuggingEngineConfigurer();
-		InterpreterConfig alteredConfig = configurer.alterConfig(launch, config);
+		InterpreterConfig alteredConfig = configurer.alterConfig(launch, config, getInstall());
 		return alteredConfig;
 	}
 }