diff --git a/auto/lib/make b/auto/lib/make
index 60cd7bc..170311c 100644
--- a/auto/lib/make
+++ b/auto/lib/make
@@ -10,6 +10,10 @@
     . auto/lib/md5/make
 fi
 
+if [ $SHA1 != NONE -a $SHA1 != NO -a $SHA1 != YES ]; then
+    . auto/lib/sha1/make
+fi
+
 if [ $OPENSSL != NONE -a $OPENSSL != NO -a $OPENSSL != YES ]; then
     . auto/lib/openssl/make
 fi