Index: cacao/configure.ac
===================================================================
--- cacao.orig/configure.ac	2008-06-27 01:23:44.000000000 +0200
+++ cacao/configure.ac	2008-06-27 01:24:02.000000000 +0200
@@ -772,6 +772,7 @@
 
 AC_CHECK_WITH_JAVA_RUNTIME_LIBRARY_PREFIX
 AC_CHECK_WITH_JAVA_RUNTIME_LIBRARY_CLASSES
+AC_CHECK_WITH_BUILD_JAVA_RUNTIME_LIBRARY_CLASSES
 
 if test x"${ENABLE_JRE_LAYOUT}" = "xno"; then
    AC_CHECK_WITH_JAVA_RUNTIME_LIBRARY_LIBDIR
Index: cacao/m4/java-runtime-library.m4
===================================================================
--- cacao.orig/m4/java-runtime-library.m4	2008-06-27 01:23:44.000000000 +0200
+++ cacao/m4/java-runtime-library.m4	2008-06-27 01:24:02.000000000 +0200
@@ -93,20 +93,32 @@
 AC_DEFINE_UNQUOTED([JAVA_RUNTIME_LIBRARY_CLASSES], "${JAVA_RUNTIME_LIBRARY_CLASSES}", [Java runtime library classes])
 AC_SUBST(JAVA_RUNTIME_LIBRARY_CLASSES)
 
+dnl where are Java core library classes located at compilation time
+
+AC_DEFUN([AC_CHECK_WITH_BUILD_JAVA_RUNTIME_LIBRARY_CLASSES],[
+AC_MSG_CHECKING(where Java core library classes are located at compile time)
+AC_ARG_WITH([build-java-runtime-library-classes],
+            [AS_HELP_STRING(--with-build-java-runtime-library-classes=<path>,path to Java core library classes (includes the name of the file and may be flat) [[default=${JAVA_RUNTIME_LIBRARY_PREFIX}/share/classpath/glibj.zip]])],
+            [BUILD_JAVA_RUNTIME_LIBRARY_CLASSES=${withval}],
+            [BUILD_JAVA_RUNTIME_LIBRARY_CLASSES=${JAVA_RUNTIME_LIBRARY_PREFIX}/share/classpath/glibj.zip])
+AC_MSG_RESULT(${BUILD_JAVA_RUNTIME_LIBRARY_CLASSES})
+AC_DEFINE_UNQUOTED([BUILD_JAVA_RUNTIME_LIBRARY_CLASSES], "${BUILD_JAVA_RUNTIME_LIBRARY_CLASSES}", [Java core library classes at compile time])
+AC_SUBST(BUILD_JAVA_RUNTIME_LIBRARY_CLASSES)
+])
+
 dnl define BOOTCLASSPATH for Makefiles
 case "${WITH_JAVA_RUNTIME_LIBRARY}" in
     cldc1.1 | gnuclasspath)
-        BOOTCLASSPATH="\$(top_builddir)/src/classes/classes:\$(JAVA_RUNTIME_LIBRARY_CLASSES)"
+        BOOTCLASSPATH="\$(top_builddir)/src/classes/classes:\$(BUILD_JAVA_RUNTIME_LIBRARY_CLASSES)"
         ;;
     *)
-        BOOTCLASSPATH="\$(JAVA_RUNTIME_LIBRARY_CLASSES)"
+        BOOTCLASSPATH="\$(BUILD_JAVA_RUNTIME_LIBRARY_CLASSES)"
         ;;
 esac
 AC_SUBST(BOOTCLASSPATH)
 ])
 
-
-dnl where are Java runtime library native libraries installed
+dnl where are Java runtime library native libraries installed (at compilation time)
 
 AC_DEFUN([AC_CHECK_WITH_JAVA_RUNTIME_LIBRARY_LIBDIR],[
 AC_MSG_CHECKING(where Java runtime library native libraries are installed)