diff -rpuN genkernel/gen_compile.sh genkernel-unionfscb/gen_compile.sh
--- genkernel/gen_compile.sh	2006-11-10 02:12:54.000000000 -0500
+++ genkernel-unionfscb/gen_compile.sh	2006-11-22 19:44:29.000000000 -0500
@@ -1,5 +1,7 @@
 #!/bin/bash
 
+. gen_unionfs_helpers.sh
+
 compile_kernel_args()
 {
 	local ARGS
@@ -318,95 +320,29 @@
 }
 
 compile_unionfs_modules() {
+	# This sets ${UNIONFS_VERSION} to the correct value.
+	get_unionfs_version
+	UNIONFS_MODULES_BINCACHE=${UNIONFS_MODULES_BINCACHE/UNIONFS_VER/${UNIONFS_VERSION}}
+	UNIONFS_BINCACHE=${UNIONFS_BINCACHE/UNIONFS_VER/${UNIONFS_VERSION}}
+	# subsitute source tarball here.
+	# the user can override this functionality by changing
+	# ${UNIONFS_SRCTAR} in /etc/genkernel.conf. genkernel can
+	# print a warning if the two versions do not match.
+	UNIONFS_SRCTAR=${UNIONFS_SRCTAR/UNIONFS_VER/${UNIONFS_VERSION}}
+	UNIONFS_DIR="unionfs-${UNIONFS_VERSION}"
 	if [ ! -f "${UNIONFS_MODULES_BINCACHE}" ]
 	then
-		[ -f "${UNIONFS_SRCTAR}" ] ||
-			gen_die "Could not find unionfs source tarball: ${UNIONFS_SRCTAR}!"
-		cd "${TEMP}"
-		rm -rf ${UNIONFS_DIR} > /dev/null
-		rm -rf unionfs > /dev/null
-		mkdir -p unionfs
-		/bin/tar -zxpf ${UNIONFS_SRCTAR} ||
-			gen_die 'Could not extract unionfs source tarball!'
-		[ -d "${UNIONFS_DIR}" ] ||
-			gen_die 'Unionfs directory ${UNIONFS_DIR} is invalid!'
-		cd "${UNIONFS_DIR}"
-		print_info 1 'unionfs modules: >> Compiling...'
-		echo "LINUXSRC=${KERNEL_DIR}" >> fistdev.mk
-		echo 'TOPINC=-I$(LINUXSRC)/include' >> fistdev.mk
-		echo "MODDIR= /lib/modules/${KV}" >> fistdev.mk
-		echo "KERNELVERSION=${KV}" >> fistdev.mk
-		# Fix for hardened/selinux systems to have extened attributes
-		# per r2d2's request.  Also add -DUNIONFS_UNSUPPORTED for 2.6.16
-		echo "EXTRACFLAGS=-DUNIONFS_XATTR -DFIST_SETXATTR_CONSTVOID -DUNIONFS_UNSUPPORTED" \
-			>> fistdev.mk
-		# Here we do something really nasty and disable debugging, along with
-		# change our default CFLAGS
-		echo "UNIONFS_DEBUG_CFLAG=-DUNIONFS_NDEBUG" >> fistdev.mk
-		echo "UNIONFS_OPT_CFLAG= -O2 -pipe" >> fistdev.mk
-
-		if [ "${PAT}" -ge '6' ]
-		then
-			cd "${TEMP}"
-			cd "${UNIONFS_DIR}"
-			# Compile unionfs module within the unionfs
-			# environment not within the kernelsrc dir
-			make unionfs.ko || gen_die 'failed to compile unionfs'
-		else
-			gen_die 'unionfs is only supported on 2.6 targets'
-		fi
-		print_info 1 'unionfs: >> Copying to cache...'
-	
-		mkdir -p ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
-		
-		if [ -f unionfs.ko ]
-		then 
-			cp -f unionfs.ko ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
-		else
-			cp -f unionfs.o ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
- 		fi
-	
-		cd ${TEMP}/unionfs
-		/bin/tar -cjf "${UNIONFS_MODULES_BINCACHE}" . ||
-			gen_die 'Could not create unionfs modules binary cache'
-	
-		cd "${TEMP}"
-		rm -rf "${UNIONFS_DIR}" > /dev/null
-		rm -rf unionfs > /dev/null
+		print_info 1 "UNIONFS: ${UNIONFS_VERSION} ${UNIONFS_SRCTAR}"
+		print_info 1 "UNIONFS callback: ${UNIONFS_COMPILE_FUNC}"
+		${UNIONFS_COMPILE_FUNC}
 	fi
 }
 
 compile_unionfs_utils() {
 	if [ ! -f "${UNIONFS_BINCACHE}" ]
 	then
-		[ -f "${UNIONFS_SRCTAR}" ] ||
-			gen_die "Could not find unionfs source tarball: ${UNIONFS_SRCTAR}!"
-		cd "${TEMP}"
-		rm -rf ${UNIONFS_DIR} > /dev/null
-		rm -rf unionfs > /dev/null
-		mkdir -p unionfs/sbin
-		/bin/tar -zxpf ${UNIONFS_SRCTAR} ||
-			gen_die 'Could not extract unionfs source tarball!'
-		[ -d "${UNIONFS_DIR}" ] ||
-			gen_die 'Unionfs directory ${UNIONFS_DIR} is invalid!'
-		cd "${UNIONFS_DIR}"
-		print_info 1 'unionfs tools: >> Compiling...'
-		sed -i Makefile -e 's|${CC} -o|${CC} -static -o|g'
-		compile_generic utils utils
-		
-		print_info 1 'unionfs: >> Copying to cache...'
-		strip uniondbg unionctl
-		cp uniondbg ${TEMP}/unionfs/sbin/ || 
-			gen_die 'Could not copy the uniondbg binary to the tmp directory'
-		cp unionctl ${TEMP}/unionfs/sbin/ ||
-			gen_die 'Could not copy the unionctl binary to the tmp directory'
-		cd ${TEMP}/unionfs	
-		/bin/tar -cjf "${UNIONFS_BINCACHE}" . ||
-			gen_die 'Could not create unionfs tools binary cache'
-		
-		cd "${TEMP}"
-		rm -rf "${UNIONFS_DIR}" > /dev/null
-		rm -rf unionfs > /dev/null
+		print_info 1 "unionfs tools callback: ${UNIONFS_COMPILE_UTILS_FUNC}"
+		${UNIONFS_COMPILE_UTILS_FUNC}
 	fi
 }
 
diff -urpN genkernel/gen_unionfs_helpers.sh genkernel-unionfscb/gen_unionfs_helpers.sh
--- genkernel/gen_unionfs_helpers.sh	1969-12-31 19:00:00.000000000 -0500
+++ genkernel-unionfscb/gen_unionfs_helpers.sh	2006-11-22 19:45:16.000000000 -0500
@@ -0,0 +1,297 @@
+#!/bin/bash
+# Daniel Casimiro <dan.casimiro@gmail.com>
+#
+
+# Emulates:  hash[key]=value
+# * This function is from:
+#     http://tldp.org/LDP/abs/html/contributed-scripts.html#HASHLIB
+#
+# Params:
+# 1 - hash
+# 2 - key
+# 3 - value
+function hash_set {
+	eval "${Hash_config_varname_prefix}${1}_${2}=\"${3}\""
+}
+
+# Emulates something similar to:
+#   foreach($hash as $key => $value) { fun($key,$value); }
+# * This function is from:
+#     http://tldp.org/LDP/abs/html/contributed-scripts.html#HASHLIB
+#
+# It is possible to write different variations of this function.
+# Here we use a function call to make it as "generic" as possible.
+#
+# Params:
+# 1 - hash
+# 2 - function name
+function hash_foreach {
+	local keyname oldIFS="$IFS"
+	IFS=' '
+	for i in $(eval "echo \${!${Hash_config_varname_prefix}${1}_*}"); do
+		keyname=$(eval "echo \${i##${Hash_config_varname_prefix}${1}_}")
+		eval "$2 $keyname \"\$$i\""
+	done
+	IFS="$oldIFS"
+}
+
+# UnionFS requires different versions for different kernels.
+# This list is as of 27 October 2006.
+# Kernel Version Compatibility:
+# Kernel Version 	Unionfs Version
+# 2.4.x (x>19) 	1.0.14
+# 2.6.x (x<9) 	Not Supported
+# 2.6.9 - 2.6.15 	1.1.5
+# 2.6.16 	1.2
+# 2.6.17 	1.3
+# 2.6.18        1.4
+# 2.6.newer 	CVS Snapshots
+
+# $1 unionfs version
+# $2 kernel version regular expression
+test_unionfs_version() {
+    MYKV=`expr match "${KV}" $2`
+    # this test can be improved...
+    if [ ${MYKV} -gt 0 ]; then
+	# The keys cannot contain '.', so underscores are substituted here.
+	UNIONFS_VERSION=${1//_/.}
+    fi
+}
+
+# set kernel versions regular expressions and unionfs versions in config file
+# build a hash that maps kernel version re's to unionfs version
+# for each hash key, use the value when the key regular expression evals
+# true when compared to ${BASEKV}
+get_unionfs_version() {
+    # Do not support 2.4 kernels yet; just need another RE.
+    # The hash is hard coded here, but it could be built from variables defined
+    # in /etc/genkernel.conf
+    hash_set unionfsversions 1_1_5      "2\.6\.\(\<1[0-5]\>\|9\)"
+    hash_set unionfsversions 1_2        "2\.6\.16"
+    hash_set unionfsversions 1_3        "2\.6\.17"
+    hash_set unionfsversions 1_4        "2\.6\.18"
+
+    # Unset the UNIONFS_VERSION that was set in /etc/genkernel.conf
+    # This function could check if the variable is set, and then break
+    # Or, it could use a different variable name
+    UNIONFS_VERSION=
+    hash_foreach unionfsversions test_unionfs_version
+
+    if [ -z ${UNIONFS_VERSION} ]; then
+	gen_die "${KV} is an invalid kernel for UNIONFS!"
+    fi
+
+    tmpunion=${UNIONFS_VERSION//./_}
+    UNIONFS_COMPILE_FUNC=compile_unionfs_modules_${tmpunion:0:3}
+    UNIONFS_COMPILE_UTILS_FUNC=compile_unionfs_utils_${tmpunion:0:3}
+}
+
+compile_unionfs_modules_1_1() {
+    [ -f "${UNIONFS_SRCTAR}" ] ||
+	gen_die "Could not find unionfs source tarball: ${UNIONFS_SRCTAR}!"
+
+    cd "${TEMP}"
+    rm -rf ${UNIONFS_DIR} > /dev/null
+    rm -rf unionfs > /dev/null
+    mkdir -p unionfs
+    /bin/tar -zxpf ${UNIONFS_SRCTAR} ||
+	gen_die 'Could not extract unionfs source tarball!'
+
+    [ -d "${UNIONFS_DIR}" ] ||
+	gen_die 'Unionfs directory ${UNIONFS_DIR} is invalid!'
+    cd "${UNIONFS_DIR}"
+    print_info 1 'unionfs modules: >> Compiling...'
+    echo "LINUXSRC=${KERNEL_DIR}" >> fistdev.mk
+    echo 'TOPINC=-I$(LINUXSRC)/include' >> fistdev.mk
+    echo "MODDIR= /lib/modules/${KV}" >> fistdev.mk
+    echo "KERNELVERSION=${KV}" >> fistdev.mk
+    # Fix for hardened/selinux systems to have extened attributes
+    # per r2d2's request.  Also add -DUNIONFS_UNSUPPORTED for 2.6.16
+    echo "EXTRACFLAGS=-DUNIONFS_XATTR -DFIST_SETXATTR_CONSTVOID -DUNIONFS_UNSUPPORTED" \
+	>> fistdev.mk
+    # Here we do something really nasty and disable debugging, along with
+    # change our default CFLAGS
+    echo "UNIONFS_DEBUG_CFLAG=-DUNIONFS_NDEBUG" >> fistdev.mk
+    echo "UNIONFS_OPT_CFLAG= -O2 -pipe" >> fistdev.mk
+
+    if [ "${PAT}" -ge '6' ]
+    then
+	cd "${TEMP}"
+	cd "${UNIONFS_DIR}"
+	sed -i Makefile -e 's|-Werror||g'
+	# Compile unionfs module within the unionfs
+	# environment not within the kernelsrc dir
+	make unionfs.ko || gen_die 'failed to compile unionfs'
+    else
+	gen_die 'unionfs is only supported on 2.6 targets'
+    fi
+    print_info 1 'unionfs: >> Copying to cache...'
+	
+    mkdir -p ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
+		
+    if [ -f unionfs.ko ]
+    then 
+	cp -f unionfs.ko ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
+    else
+	cp -f unionfs.o ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
+    fi
+	
+    cd ${TEMP}/unionfs
+    /bin/tar -cjf "${UNIONFS_MODULES_BINCACHE}" . ||
+	gen_die 'Could not create unionfs modules binary cache'
+	
+    cd "${TEMP}"
+    rm -rf "${UNIONFS_DIR}" > /dev/null
+    rm -rf unionfs > /dev/null
+}
+
+compile_unionfs_modules_1_2() {
+    compile_unionfs_modules_1_1
+}
+
+compile_unionfs_modules_1_3() {
+    [ -f "${UNIONFS_SRCTAR}" ] ||
+	gen_die "Could not find unionfs source tarball: ${UNIONFS_SRCTAR}!"
+
+    cd "${TEMP}"
+    rm -rf ${UNIONFS_DIR} > /dev/null
+    rm -rf unionfs* > /dev/null
+    mkdir unionfs
+    /bin/tar xzpf ${UNIONFS_SRCTAR} ||
+	gen_die 'Could not extract unionfs source tarball!'
+
+    [ -d "${UNIONFS_DIR}" ] ||
+	gen_die 'Unionfs directory ${UNIONFS_DIR} is invalid!'
+    cd "${UNIONFS_DIR}"
+    print_info 1 'unionfs modules: >> Compiling...'
+    echo "LINUXSRC=${KERNEL_DIR}" >> fistdev.mk
+    echo 'TOPINC=-I$(LINUXSRC)/include' >> fistdev.mk
+    echo "MODDIR= /lib/modules/${KV}" >> fistdev.mk
+    echo "KVERS=${KV}" >> fistdev.mk
+    echo "KERNELVERSION=${KV}" >> fistdev.mk
+    # Fix for hardened/selinux systems to have extened attributes
+    # per r2d2's request.  Also add -DUNIONFS_UNSUPPORTED for 2.6.16
+    echo "EXTRACFLAGS=-DUNIONFS_XATTR -DFIST_SETXATTR_CONSTVOID -DUNIONFS_UNSUPPORTED" \
+	>> fistdev.mk
+    # Here we do something really nasty and disable debugging, along with
+    # change our default CFLAGS
+    echo "UNIONFS_DEBUG_CFLAG=-DUNIONFS_NDEBUG" >> fistdev.mk
+    echo "UNIONFS_OPT_CFLAG= -O2 -pipe" >> fistdev.mk
+
+    if [ "${PAT}" -ge '6' ]
+    then
+	# ARCH is used by unionfs - and conflicts with genkernel
+	ARCH_PUSH=${ARCH}
+	unset ARCH
+	#sed -i Makefile -e 's|-Werror||g'
+	# Compile unionfs module within the unionfs
+	# environment not within the kernelsrc dir
+	make unionfs.ko || gen_die 'failed to compile unionfs'
+	ARCH=${ARCH_PUSH}
+    else
+	gen_die 'unionfs is only supported on 2.6 targets'
+    fi
+    print_info 1 'unionfs: >> Copying to cache...'
+	
+    mkdir -p ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
+		
+    if [ -f unionfs.ko ]
+    then 
+	cp -f unionfs.ko ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
+    else
+	cp -f unionfs.o ${TEMP}/unionfs/lib/modules/${KV}/kernel/fs/unionfs
+    fi
+	
+    cd ${TEMP}/unionfs
+    /bin/tar -cjf "${UNIONFS_MODULES_BINCACHE}" . ||
+	gen_die 'Could not create unionfs modules binary cache'
+	
+    cd "${TEMP}"
+    rm -rf "${UNIONFS_DIR}" > /dev/null
+    rm -rf unionfs* > /dev/null
+}
+
+compile_unionfs_modules_1_4() {
+    compile_unionfs_modules_1_3
+}
+
+# uniofs_utils
+compile_unionfs_utils_1_1() {
+	if [ ! -f "${UNIONFS_BINCACHE}" ]
+	then
+		[ -f "${UNIONFS_SRCTAR}" ] ||
+			gen_die "Could not find unionfs source tarball: ${UNIONFS_SRCTAR}!"
+		cd "${TEMP}"
+		rm -rf ${UNIONFS_DIR} > /dev/null
+		rm -rf unionfs > /dev/null
+		mkdir -p unionfs/sbin
+		/bin/tar -zxpf ${UNIONFS_SRCTAR} ||
+			gen_die 'Could not extract unionfs source tarball!'
+		[ -d "${UNIONFS_DIR}" ] ||
+			gen_die 'Unionfs directory ${UNIONFS_DIR} is invalid!'
+		cd "${UNIONFS_DIR}"
+		print_info 1 'unionfs tools: >> Compiling...'
+		sed -i Makefile -e 's|${CC} -o|${CC} -static -o|g'
+		compile_generic utils utils
+		
+		print_info 1 'unionfs: >> Copying to cache...'
+		strip uniondbg unionctl
+		cp uniondbg ${TEMP}/unionfs/sbin/ || 
+			gen_die 'Could not copy the uniondbg binary to the tmp directory'
+		cp unionctl ${TEMP}/unionfs/sbin/ ||
+			gen_die 'Could not copy the unionctl binary to the tmp directory'
+		cd ${TEMP}/unionfs	
+		/bin/tar -cjf "${UNIONFS_BINCACHE}" . ||
+			gen_die 'Could not create unionfs tools binary cache'
+		
+		cd "${TEMP}"
+		rm -rf "${UNIONFS_DIR}" > /dev/null
+		rm -rf unionfs > /dev/null
+	fi
+}
+
+compile_unionfs_utils_1_2() {
+    compile_unionfs_utils_1_1
+}
+
+compile_unionfs_utils_1_3() {
+	if [ ! -f "${UNIONFS_BINCACHE}" ]
+	then
+		[ -f "${UNIONFS_SRCTAR}" ] ||
+			gen_die "Could not find unionfs source tarball: ${UNIONFS_SRCTAR}!"
+		cd "${TEMP}"
+		rm -rf ${UNIONFS_DIR} > /dev/null
+		rm -rf unionfs > /dev/null
+		mkdir -p unionfs/sbin
+		/bin/tar -zxpf ${UNIONFS_SRCTAR} ||
+			gen_die 'Could not extract unionfs source tarball!'
+		[ -d "${UNIONFS_DIR}" ] ||
+			gen_die 'Unionfs directory ${UNIONFS_DIR} is invalid!'
+		cd "${UNIONFS_DIR}"
+		print_info 1 'unionfs tools: >> Compiling...'
+		sed -i utils/Makefile -e 's|${CC} -o|${CC} -static -o|g'
+		sed -i Makefile -e 's|${CC} -o|${CC} -static -o|g'
+		compile_generic utils utils
+
+		print_info 1 'moving into utils directory...'
+		cd utils
+
+		print_info 1 'unionfs: >> Copying to cache...'
+		strip uniondbg unionctl
+		cp uniondbg ${TEMP}/unionfs/sbin/ || 
+			gen_die 'Could not copy the uniondbg binary to the tmp directory'
+		cp unionctl ${TEMP}/unionfs/sbin/ ||
+			gen_die 'Could not copy the unionctl binary to the tmp directory'
+		cd ${TEMP}/unionfs	
+		/bin/tar -cjf "${UNIONFS_BINCACHE}" . ||
+			gen_die 'Could not create unionfs tools binary cache'
+		
+		cd "${TEMP}"
+		rm -rf "${UNIONFS_DIR}" > /dev/null
+		rm -rf unionfs > /dev/null
+	fi
+}
+
+compile_unionfs_utils_1_4() {
+    compile_unionfs_utils_1_3
+}