diff --git a/envsetup.sh b/envsetup.sh
index c572c16..e0b2c62 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -82,6 +82,7 @@
 
     if (echo -n $1 | grep -q -e "^cm_") ; then
        CM_BUILD=$(echo -n $1 | sed -e 's/^cm_//g')
+       export BUILD_NUMBER=$((date +%s%N ; echo $CM_BUILD; hostname) | openssl sha1 | sed -e 's/.*=//g; s/ //g' | cut -c1-10)
     else
        CM_BUILD=
     fi