diff --git a/calendar/base/src/Makefile.in b/calendar/base/src/Makefile.in
index 1e7d19bcdd..9e2cf7ab9a 100644
--- a/calendar/base/src/Makefile.in
+++ b/calendar/base/src/Makefile.in
@@ -14,7 +14,6 @@ MODULE           = calbase
 LIBRARY_NAME     = calbase_s
 MODULE_NAME      = calBaseModule
 FORCE_STATIC_LIB = 1
-GRE_MODULE       = 1
 FORCE_USE_PIC   = 1 # Force use of PIC
 USE_STATIC_LIBS = 1
 
diff --git a/calendar/libical/src/libical/Makefile.in b/calendar/libical/src/libical/Makefile.in
index 2016fb0f95..513d0eeba4 100644
--- a/calendar/libical/src/libical/Makefile.in
+++ b/calendar/libical/src/libical/Makefile.in
@@ -47,7 +47,6 @@ MODULE           = ical
 LIBRARY_NAME     = mozical
 MODULE_NAME      = mozIcalModule
 FORCE_STATIC_LIB = 1
-GRE_MODULE       = 1
 FORCE_USE_PIC    = 1 # Force use of PIC
 USE_STATIC_LIBS  = 1
 
diff --git a/config/rules.mk b/config/rules.mk
index 64c899525c..a71dc83477 100644
--- a/config/rules.mk
+++ b/config/rules.mk
@@ -1283,14 +1283,14 @@ $(foreach namespace,$(EXPORTS_NAMESPACES),$(eval $(EXPORT_NAMESPACE_RULE)))
 ################################################################################
 # Copy each element of PREF_JS_EXPORTS
 
-ifdef GRE_MODULE
-PREF_DIR = greprefs
-else
-ifneq (,$(XPI_NAME)$(LIBXUL_SDK))
-PREF_DIR = defaults/preferences
-else
+# The default location for PREF_JS_EXPORTS is the gre prefs directory.
 PREF_DIR = defaults/pref
-endif
+
+# If DIST_SUBDIR is defined it indicates that app and gre dirs are
+# different and that we are building app related resources. Hence,
+# PREF_DIR should point to the app prefs location.
+ifneq (,$(DIST_SUBDIR)$(XPI_NAME)$(LIBXUL_SDK))
+PREF_DIR = defaults/preferences
 endif
 
 ifneq ($(PREF_JS_EXPORTS),)
diff --git a/db/mork/build/Makefile.in b/db/mork/build/Makefile.in
index 056359c155..6609430ad9 100644
--- a/db/mork/build/Makefile.in
+++ b/db/mork/build/Makefile.in
@@ -21,7 +21,6 @@ MOZILLA_INTERNAL_API = 1
 LIBXUL_LIBRARY	= 1
 else
 FORCE_SHARED_LIB = 1
-GRE_MODULE	= 1
 endif
 
 CPPSRCS		= nsMorkFactory.cpp
diff --git a/ldap/xpcom/src/Makefile.in b/ldap/xpcom/src/Makefile.in
index b7807f03a6..e0d6b1771b 100644
--- a/ldap/xpcom/src/Makefile.in
+++ b/ldap/xpcom/src/Makefile.in
@@ -21,7 +21,6 @@ MOZILLA_INTERNAL_API = 1
 LIBXUL_LIBRARY	= 1
 else
 FORCE_SHARED_LIB = 1
-GRE_MODULE	= 1
 endif
 
 EXTRA_COMPONENTS = \
diff --git a/mailnews/build/Makefile.in b/mailnews/build/Makefile.in
index be5832e10f..25a1afe929 100644
--- a/mailnews/build/Makefile.in
+++ b/mailnews/build/Makefile.in
@@ -20,7 +20,6 @@ LIBXUL_LIBRARY	= 1
 else
 FORCE_SHARED_LIB = 1
 endif
-GRE_MODULE	= 1
 FORCE_USE_PIC   = 1
 
 MODULE_NAME	= nsMailModule