diff --git a/Install-unix.txt b/Install-unix.txt
index 8a9c65a..4a50064 100644
--- a/Install-unix.txt
+++ b/Install-unix.txt
@@ -345,6 +345,10 @@
optimization and debug flags (default -g -O2). Antique C++ compilers
will normally be rejected by configure tests so specifying this option
should only be necessary if Magick++ fails to compile.
+
+ --with-package-release-name
+ encode this name into the shared library name (see libtools -release
+ option).
--without-perl
disable build/install of PerlMagick, or