diff --git a/images/base/Dockerfile b/images/base/Dockerfile
index 9770d47..14c2724 100644
--- a/images/base/Dockerfile
+++ b/images/base/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:20.04
+FROM ubuntu:21.04
 
 ENV DEBIAN_FRONTEND noninteractive
 
diff --git a/scripts.d/50-xvid.sh b/scripts.d/50-xvid.sh
index ca5fe14..eb26655 100755
--- a/scripts.d/50-xvid.sh
+++ b/scripts.d/50-xvid.sh
@@ -17,6 +17,14 @@ ffbuild_dockerbuild() {
 
     cd build/generic
 
+    # The original code fails on a two-digit major...
+    sed -i\
+        -e 's/GCC_MAJOR=.*/GCC_MAJOR=10/' \
+        -e 's/GCC_MINOR=.*/GCC_MINOR=0/' \
+        configure.in
+
+    ./bootstrap.sh
+
     local myconf=(
         --prefix="$FFBUILD_PREFIX"
     )