Document where to find horde-db-migrate.

horde/docs/INSTALL

@@ -681,9 +681,27 @@ Configuring Horde
    configuration to already exist, and the configured database user to have
    sufficient permissions to create new tables in this database.
 
-   Alternatively you can run the ``bin/horde-db-migrate`` script in the Horde
+   Alternatively you can run the ``horde-db-migrate`` script in the Horde
    directory from the command line.
 
+   If you installed Horde into the global PEAR system, this script should be in
+   your command path. If the script cannot be found in your path, you need to
+   specify the full path to the script, e.g.::
+
+      /var/www/horde/pear/horde-db-migrate
+
+   You can use the ``pear`` command to find the place where the script has been
+   installed::
+
+      pear config-get bin_dir
+
+   If you installed into a local PEAR installation, you need to tell PHP and
+   PEAR where to find the installation and the script, e.g.::
+
+      PHP_PEAR_SYSCONF_DIR=/var/www/horde php \
+          -d include_path=/var/www/horde/pear/php \
+          /var/www/horde/pear/horde-db-migrate
+
 5. Setting up alarm emails
 
    If you want your users to be able to receive emails from the Horde_Alarm