diff --git a/targets/support/chroot-functions.sh b/targets/support/chroot-functions.sh
index 456ae4c..bcb22f4 100755
--- a/targets/support/chroot-functions.sh
+++ b/targets/support/chroot-functions.sh
@@ -21,6 +21,7 @@ check_genkernel_version(){
 	if [ -x /usr/bin/genkernel ]
 	then
 		genkernel_version=$(genkernel --version)
+		genkernel_version=${genkernel_version//[^0-9\.]/}	# keep just numbers and dots
 		genkernel_version_major=${genkernel_version%%.*}
 		genkernel_version_minor_sub=${genkernel_version#${genkernel_version_major}.}
 		genkernel_version_minor=${genkernel_version_minor_sub%%.*}