INSTALL in mahoro-0.3 vs INSTALL in mahoro-0.4

@@ -1,6 +1,28 @@
- INSTALL
-=========
+libmagic installation
+=====================
+
+Mahoro is a wrapper around libmagic[1], so it needs the libmagic
+development headers and libraries to run.  If your operating system
+provides libmagic development libraries and headers, you will not need
+the "--with-magic*" command-line options below.
+
+For Debian-based systems: apt-get install libmagic-dev
+For CentOS 6.x or similar RPM-based systems: yum install file-devel
+For CentOS 5.x or similar RPM-based systems: yum install file
+
+[1] - https://en.wikipedia.org/wiki/Libmagic
+
+INSTALL (from RubyGems)
+=======================
+
+The installation is simple, install libmagic and type the following:
+
+# gem install mahoro -- --with-magic-include=/path/to/include \
+                        --with-magic-lib=/path/to/lib
+
+INSTALL (from tarball)
+======================
 
 The installation is simple, install libmagic and type the following.
 
 > ruby extconf.rb --with-magic-include=/path/to/include \
                   --with-magic-lib=/path/to/lib