--- pym/portage.py	(revision 9281)
+++ pym/portage.py	(revision 9282)
@@ -1021,7 +1021,7 @@ 
 		"PORTAGE_IUSE",
 		"PORTAGE_LOG_FILE", "PORTAGE_MASTER_PID",
 		"PORTAGE_PYM_PATH", "PORTAGE_REPO_NAME", "PORTAGE_RESTRICT",
-		"PORTAGE_TMPDIR", "PORTAGE_WORKDIR_MODE",
+		"PORTAGE_TMPDIR", "PORTAGE_UPDATE_ENV", "PORTAGE_WORKDIR_MODE",
 		"PORTDIR", "PORTDIR_OVERLAY", "PREROOTPATH", "PROFILE_PATHS",
 		"ROOT", "ROOTPATH", "STARTDIR", "T", "TMP", "TMPDIR",
 		"USE_EXPAND", "USE_ORDER", "WORKDIR",
@@ -9133,8 +9133,12 @@ 
 		del conf_mem_file
 
 		#do postinst script
+		self.settings["PORTAGE_UPDATE_ENV"] = \
+			os.path.join(self.dbpkgdir, "environment.bz2")
+		self.settings.backup_changes("PORTAGE_UPDATE_ENV")
 		a = doebuild(myebuild, "postinst", destroot, self.settings, use_cache=0,
 			tree=self.treetype, mydbapi=mydbapi, vartree=self.vartree)
+		self.settings.pop("PORTAGE_UPDATE_ENV", None)
 
 		# XXX: Decide how to handle failures here.
 		if a != os.EX_OK:
--- bin/isolated-functions.sh	(revision 9281)
+++ bin/isolated-functions.sh	(revision 9282)
@@ -470,7 +470,8 @@ 
 			PORTAGE_COLORMAP PORTAGE_CONFIGROOT PORTAGE_DEBUG \
 			PORTAGE_DEPCACHEDIR PORTAGE_GID PORTAGE_INST_GID \
 			PORTAGE_INST_UID PORTAGE_LOG_FILE PORTAGE_MASTER_PID \
-			PORTAGE_REPO_NAME PORTAGE_RESTRICT PORTAGE_WORKDIR_MODE PORTDIR \
+			PORTAGE_REPO_NAME PORTAGE_RESTRICT PORTAGE_UPDATE_ENV \
+			PORTAGE_WORKDIR_MODE PORTDIR \
 			PORTDIR_OVERLAY ${!PORTAGE_SANDBOX_*} PREROOTPATH \
 			PROFILE_PATHS PWORKDIR QA_INTERCEPTORS \
 			RC_DEFAULT_INDENT RC_DOT_PATTERN RC_ENDCOL \
--- bin/ebuild.sh	(revision 9281)
+++ bin/ebuild.sh	(revision 9282)
@@ -1777,6 +1777,16 @@ 
 			ebuild_phase_with_hooks pkg_${EBUILD_SH_ARGS}
 			set +x
 		fi
+		if [[ $EBUILD_PHASE == postinst ]] && [[ -n $PORTAGE_UPDATE_ENV ]]; then
+			# Update environment.bz2 in case installation phases
+			# need to pass some variables to uninstallation phases.
+			(
+				unset S _E_DOCDESTTREE_ _E_EXEDESTTREE_
+				save_ebuild_env | filter_readonly_variables \
+					--filter-sandbox --allow-extra-vars | \
+					bzip2 -c -f9 > "$PORTAGE_UPDATE_ENV"
+			)
+		fi
 		;;
 	unpack|compile|test|clean|install)
 		if [ "${SANDBOX_DISABLED="0"}" == "0" ]; then