diff -uNrp misc/mozilla/security/coreconf/config.mk misc/build/mozilla/security/coreconf/config.mk
--- misc/mozilla/security/coreconf/config.mk	2008-06-15 19:22:15.000000000 -0300
+++ misc/build/mozilla/security/coreconf/config.mk	2011-12-14 22:27:52.383209720 -0300
@@ -63,7 +63,7 @@ endif
 #######################################################################
 
 TARGET_OSES = FreeBSD BSD_OS NetBSD OpenUNIX OS2 QNX Darwin BeOS OpenBSD \
-              OpenVMS AIX
+              OpenVMS AIX Linux
 
 ifeq (,$(filter-out $(TARGET_OSES),$(OS_TARGET)))
 include $(CORE_DEPTH)/coreconf/$(OS_TARGET).mk
diff -uNrp misc/mozilla/security/coreconf/Linux.mk misc/build/mozilla/security/coreconf/Linux.mk
--- misc/mozilla/security/coreconf/Linux.mk	2011-12-14 22:26:12.391200222 -0300
+++ misc/build/mozilla/security/coreconf/Linux.mk	2011-12-14 22:29:30.183219009 -0300
@@ -177,3 +177,19 @@ G++INCLUDES		= -I/usr/include/g++
 # Always set CPU_TAG on Linux, OpenVMS, WINCE.
 #
 CPU_TAG = _$(CPU_ARCH)
+
+OS_REL_CFLAGS   += -DLINUX2_1
+MKSHLIB         = $(CC) $(DSO_LDOPTS) -Wl,-soname -Wl,$(@:$(OBJDIR)/%.so=%.so) $(RPATH)
+
+ifdef MAPFILE
+	MKSHLIB += -Wl,--version-script,$(MAPFILE)
+endif
+PROCESS_MAP_FILE = grep -v ';-' $< | \
+        sed -e 's,;+,,' -e 's; DATA ;;' -e 's,;;,,' -e 's,;.*,;,' > $@
+
+ifeq ($(OS_RELEASE),2.4)
+# Softoken 3.13 uses NO_FORK_CHECK only.
+# Softoken 3.12 uses NO_FORK_CHECK and NO_CHECK_FORK.
+# Don't use NO_CHECK_FORK in new code.
+DEFINES += -DNO_FORK_CHECK -DNO_CHECK_FORK
+endif