diff --git a/Projects/AthDataQuality/build_externals.sh b/Projects/AthDataQuality/build_externals.sh
index d5e0794689ef5ec8c41011bcbff983ef6905d7a7..848619a66d1594a8898491e5e87890c831b98b11 100755
--- a/Projects/AthDataQuality/build_externals.sh
+++ b/Projects/AthDataQuality/build_externals.sh
@@ -22,6 +22,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3")
 while getopts ":t:b:fch" opt; do
     case $opt in
         t)
diff --git a/Projects/AthGeneration/build_externals.sh b/Projects/AthGeneration/build_externals.sh
index 04f619e34bc83cdbc7a08359cee8fe3c269719ee..91b6fd9b743f36b3ea8e28a3f937eebb28d39581 100755
--- a/Projects/AthGeneration/build_externals.sh
+++ b/Projects/AthGeneration/build_externals.sh
@@ -24,7 +24,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
-EXTRACMAKE=()
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3")
 while getopts ":t:b:x:fch" opt; do
     case $opt in
         t)
diff --git a/Projects/AthSimulation/build_externals.sh b/Projects/AthSimulation/build_externals.sh
index 0463ba13158ff7881e2acae50f4bdf4b27b2abd0..96ec95ad708cb938716fb73a6f51d432321c0366 100755
--- a/Projects/AthSimulation/build_externals.sh
+++ b/Projects/AthSimulation/build_externals.sh
@@ -24,7 +24,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
-EXTRACMAKE=()
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3")
 while getopts ":t:b:x:fch" opt; do
     case $opt in
         t)
diff --git a/Projects/Athena/build_externals.sh b/Projects/Athena/build_externals.sh
index 95720fa9c0037ca4c6114b7fed107b626564c082..8cbe9cb809a151fdfba71bbc8ec44edff031c2c2 100755
--- a/Projects/Athena/build_externals.sh
+++ b/Projects/Athena/build_externals.sh
@@ -24,7 +24,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
-EXTRACMAKE=()
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3")
 while getopts ":t:b:x:fch" opt; do
     case $opt in
         t)