Thought I would share this with everyone that might run into this problem.
When trying to install on a server running 5.3.8 the installer would fail because of PHP deprecated errors.
The main error that kept me from completing the install was the session_register() which is deprecated in php 5.3. All I did was comment that line out.
Here is a list of deprecated functions in php 5.3
call_user_method() (use call_user_func() instead)
call_user_method_array() (use call_user_func_array() instead)
ereg() (use preg_match() instead)
ereg_replace() (use preg_replace() instead)
eregi() (use preg_match() with the ‘i’ modifier instead)
eregi_replace() (use preg_replace() with the ‘i’ modifier instead)
set_magic_quotes_runtime() and its alias, magic_quotes_runtime()
session_register() (use the $_SESSION superglobal instead)
session_unregister() (use the $_SESSION superglobal instead)
session_is_registered() (use the $_SESSION superglobal instead)
set_socket_blocking() (use stream_set_blocking() instead)
split() (use preg_split() instead)
spliti() (use preg_split() with the ‘i’ modifier instead)
mysql_db_query() (use mysql_select_db() and mysql_query() instead)
mysql_escape_string() (use mysql_real_escape_string() instead)
Passing locale category names as strings is now deprecated. Use the LC_* family of constants instead.
The is_dst parameter to mktime(). Use the new timezone handling functions instead.
If anyone wanted to run DF on 5.3 + then they would need to go through every file like I did and replace all the ereg, eregi, split and of course get rid of that session_register in the install.
I too am having issues installing DF 18.104.22.168 on a customer's hosting. There host has PHP 5.3.3 installed. I get the correct index page to show stating that I don't have DF installed and that I need to but when I go to the install.php file I get some goofy encrypted text when viewing in the browser.
I've downloaded the zip and unarchived in on Ubuntu and Windows 7, uploaded using Filezilla on both OSes, and still getting the error with any web browser.
Server specs (Server OS / Apache / MySQL / PHP / DragonflyCMS):
CentOS, Apache 2.2, MySQL 5.0, PHP 5.3, CPG 22.214.171.124