diff --git a/build/jam/FileRules b/build/jam/FileRules
index f0c678a6a8..261e9fcb68 100644
--- a/build/jam/FileRules
+++ b/build/jam/FileRules
@@ -377,23 +377,29 @@ actions CopySetHaikuRevision1
 
 rule DetermineHaikuRevision
 {
-	# If existing, make the target depend on the .git/index file in the
-	# root directory, so it gets updated when the revision changes due to
-	# commits or merges.
-	local gitIndex = <haiku-rootdir-git>index ;
+	# If existing, make the target depend on the $GIT_DIR/index file,
+	# so it gets updated when the revision changes due to commits or merges.
+	# If GIT_DIR is not set, fall back to .git/index.
+	local dotGit = <haiku-rootdir>.git ;
 	local revisionFile = <haiku-rootdir>haiku-revision ;
-	if ! [ on $(gitIndex) return $(HAIKU_GIT_REVISION_DETERMINED) ] {
-		HAIKU_GIT_REVISION_DETERMINED on $(gitIndex) = 1 ;
+	if ! [ on $(dotGit) return $(HAIKU_GIT_REVISION_DETERMINED) ] {
+		HAIKU_GIT_REVISION_DETERMINED on $(dotGit) = 1 ;
 		MakeLocate $(revisionFile) : $(HAIKU_BUILD_OUTPUT_DIR) ;
 		LocalClean clean : $(revisionFile) ;
 		if $(HAIKU_REVISION) {
 			DetermineHaikuRevision2 $(revisionFile) ;
+		} else if $(GIT_DIR) && $(GIT_DIR) != ".git" {
+			local gitIndex = <$(GIT_DIR)>index ;
+			SEARCH on $(gitIndex) = [ FDirName $(GIT_DIR) ] ;
+			Depends $(revisionFile) : $(gitIndex) ;
+			DetermineHaikuRevision1 $(revisionFile) : $(gitIndex) ;
 		} else if [ Glob [ FDirName $(HAIKU_TOP) .git ] : index ] {
+			local gitIndex = <haiku-rootdir-git>index ;
 			SEARCH on $(gitIndex) = [ FDirName $(HAIKU_TOP) .git ] ;
 			Depends $(revisionFile) : $(gitIndex) ;
 			DetermineHaikuRevision1 $(revisionFile) : $(gitIndex) ;
 		} else {
-			revisionFile = ;
+			Exit "ERROR: Haiku revision could not be determined." ;
 		}
 	}
 
diff --git a/configure b/configure
index fcabba206d..29d21a1574 100755
--- a/configure
+++ b/configure
@@ -565,6 +565,7 @@ fi
 # backup the passed arguments
 configureArgs="$@"
 configurePath=$0
+configureDir=`dirname $configurePath`
 
 # backup relevant environs
 configureEnvirons=
@@ -635,6 +636,7 @@ fi
 
 # exported (BuildSetup) default parameter values
 #
+GIT_DIR=`git -C "$configureDir" rev-parse --git-dir | sed 's/^gitdir: //'`
 HOST_GCC_RAW_VERSION=`$CC -dumpversion`
 HOST_CC_IS_LEGACY_GCC=`is_legacy_gcc $HOST_GCC_RAW_VERSION`
 HOST_GCC_MACHINE=`$CC -dumpmachine`
@@ -1102,6 +1104,8 @@ cat << EOF > "$buildConfigFile"
 #e ${configureEnvirons}
 #a ${configureArgs}
 
+GIT_DIR						?= "${GIT_DIR}" ;
+
 HOST_PLATFORM				?= "${HOST_PLATFORM}" ;
 TARGET_PLATFORM 			?= "${TARGET_PLATFORM}" ;
 HAIKU_PACKAGING_ARCHS		?= ${HAIKU_PACKAGING_ARCHS} ;