diff --git a/build/scripts/determine_haiku_revision b/build/scripts/determine_haiku_revision
index 0796c8c2e0..3d175fc43c 100755
--- a/build/scripts/determine_haiku_revision
+++ b/build/scripts/determine_haiku_revision
@@ -24,18 +24,21 @@ export LC_ALL=C
 
 localRev=`git rev-parse HEAD`
 
-# only determine the haiku-revision if anything has changed from
+# only determine the haiku-revision if anything has changed from the
 # last build
 if [ -z "$revision" -o "$lastBuiltRevision" != "$localRev" ]; then
 	# the revision we use is the description of HEAD with respect to the
 	# last reachable hrev-(haiku-revision-)tag
-	revision=`git describe --dirty --tags --match=hrev*`
+	revision=`git describe --dirty --tags --match=hrev* --abbrev=1`
 	if [ -z "$revision" ]; then
 		# failed to find any hrev tags, bail out
 		echo "Error: you are using a Haiku clone without tags, please set"
 		echo "       the revision tag to use (e.g. HAIKU_REVISION=hrev43210)"
 		exit 1
-	elif echo "$revision" | grep -- '-' >/dev/null; then
+	fi
+
+	revision=`echo $revision | sed 's/-g.....//' | sed 's/-/+/g'`
+	if echo "$revision" | grep -- '-' >/dev/null; then
 		# HEAD is not directly a changeset from Haiku's central repo, so we
 		# add the current branch name as additional info
 		branchName=`git branch | grep '*' | cut -b 3-`