--- old/make/common/shared/Defs-java.gmk	2009-08-18 17:12:07.639029042 +0100
+++ new/make/common/shared/Defs-java.gmk	2009-08-18 17:12:07.568013088 +0100
@@ -179,7 +179,9 @@
 ifeq ($(COMPILER_WARNINGS_FATAL), true)
   BOOT_JAVACFLAGS  += -Werror
 endif
-BOOT_JAVACFLAGS  += -encoding ascii
+BOOT_SOURCE_LANGUAGE_VERSION = 6
+BOOT_TARGET_CLASS_VERSION = 6
+BOOT_JAVACFLAGS  += -encoding ascii -source $(BOOT_SOURCE_LANGUAGE_VERSION) -target $(BOOT_TARGET_CLASS_VERSION)
 
 BOOT_JAVA_CMD      = $(BOOTDIR)/bin/java $(JAVA_TOOLS_FLAGS)
 BOOT_JAVAC_CMD     = $(BOOTDIR)/bin/javac $(JAVAC_JVM_FLAGS) $(BOOT_JAVACFLAGS)