PHP を導入します。
先人の導入例を参考にしております。

root@meckk:~# aptitude -y install php5 php5-cgi libapache2-mod-php5 php5-common php-pear 
The following NEW packages will be installed:
  apache2-mpm-prefork{ab} libapache2-mod-php5 libonig2{a} libqdbm14{a} libxml2{a} php-pear php5 php5-cgi php5-cli{a}
  php5-common php5-suhosin{a} sgml-base{a} ucf{a} xml-core{a}
0 packages upgraded, 14 newly installed, 0 to remove and 0 not upgraded.
Need to get 13.6 MB of archives. After unpacking 36.0 MB will be used.
The following packages have unmet dependencies:
  apache2-mpm-prefork: Conflicts: apache2-mpm which is a virtual package.
  apache2-mpm-worker: Conflicts: apache2-mpm which is a virtual package.
The following actions will resolve these dependencies:

     Remove the following packages:
1)     apache2-mpm-worker



The following NEW packages will be installed:
  apache2-mpm-prefork{a} libapache2-mod-php5 libonig2{a} libqdbm14{a} libxml2{a} php-pear php5 php5-cgi php5-cli{a}
  php5-common php5-suhosin{a} sgml-base{a} ucf{a} xml-core{a}
The following packages will be REMOVED:
  apache2-mpm-worker{a}
0 packages upgraded, 14 newly installed, 1 to remove and 0 not upgraded.
Need to get 13.6 MB of archives. After unpacking 36.0 MB will be used.
Get:1 http://ftp.jp.debian.org/debian/ squeeze/main apache2-mpm-prefork armel 2.2.16-6+squeeze7 [2320 B]
Get:2 http://ftp.jp.debian.org/debian/ squeeze/main libxml2 armel 2.7.8.dfsg-2+squeeze3 [818 kB]
Get:3 http://ftp.jp.debian.org/debian/ squeeze/main ucf all 3.0025+nmu1 [69.6 kB]
Get:4 http://ftp.jp.debian.org/debian/ squeeze/main libonig2 armel 5.9.1-1 [128 kB]
Get:5 http://ftp.jp.debian.org/debian/ squeeze/main libqdbm14 armel 1.8.77-4 [126 kB]
Get:6 http://ftp.jp.debian.org/debian/ squeeze/main php5-common armel 5.3.3-7+squeeze8 [552 kB]
Get:7 http://ftp.jp.debian.org/debian/ squeeze/main libapache2-mod-php5 armel 5.3.3-7+squeeze8 [2866 kB]
Get:8 http://ftp.jp.debian.org/debian/ squeeze/main php5-cli armel 5.3.3-7+squeeze8 [2851 kB]
Get:9 http://ftp.jp.debian.org/debian/ squeeze/main php-pear all 5.3.3-7+squeeze8 [365 kB]
Get:10 http://ftp.jp.debian.org/debian/ squeeze/main php5-cgi armel 5.3.3-7+squeeze8 [5701 kB]
Get:11 http://ftp.jp.debian.org/debian/ squeeze/main php5 all 5.3.3-7+squeeze8 [1062 B]
Get:12 http://ftp.jp.debian.org/debian/ squeeze/main php5-suhosin armel 0.9.32.1-1 [90.0 kB]
Get:13 http://ftp.jp.debian.org/debian/ squeeze/main sgml-base all 1.26+nmu1 [11.9 kB]
Get:14 http://ftp.jp.debian.org/debian/ squeeze/main xml-core all 0.13 [23.4 kB]
Fetched 13.6 MB in 2min 30s (90.1 kB/s)
Preconfiguring packages ...
dpkg: apache2-mpm-worker: dependency problems, but removing anyway as you requested:
 apache2 depends on apache2-mpm-worker (= 2.2.16-6+squeeze7) | apache2-mpm-prefork (= 2.2.16-6+squeeze7) | apache2-mpm-event (= 2.2.16-6+squeeze7) | apache2-mpm-itk (= 2.2.16-6+squeeze7); however:
  Package apache2-mpm-worker is to be removed.
  Package apache2-mpm-prefork is not installed.
  Package apache2-mpm-event is not installed.
  Package apache2-mpm-itk is not installed.
(Reading database ... 11653 files and directories currently installed.)
Removing apache2-mpm-worker ...
Stopping web server: apache2apache2: apr_sockaddr_info_get() failed for meckk
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for ServerName
 ... waiting .
Selecting previously deselected package apache2-mpm-prefork.
(Reading database ... 11648 files and directories currently installed.)
Unpacking apache2-mpm-prefork (from .../apache2-mpm-prefork_2.2.16-6+squeeze7_armel.deb) ...
Setting up apache2-mpm-prefork (2.2.16-6+squeeze7) ...
Starting web server: apache2apache2: apr_sockaddr_info_get() failed for meckk
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for ServerName
.
Selecting previously deselected package libxml2.
(Reading database ... 11653 files and directories currently installed.)
Unpacking libxml2 (from .../libxml2_2.7.8.dfsg-2+squeeze3_armel.deb) ...
Selecting previously deselected package ucf.
Unpacking ucf (from .../ucf_3.0025+nmu1_all.deb) ...
Moving old data out of the way
Selecting previously deselected package libonig2.
Unpacking libonig2 (from .../libonig2_5.9.1-1_armel.deb) ...
Selecting previously deselected package libqdbm14.
Unpacking libqdbm14 (from .../libqdbm14_1.8.77-4_armel.deb) ...
Selecting previously deselected package php5-common.
Unpacking php5-common (from .../php5-common_5.3.3-7+squeeze8_armel.deb) ...
Selecting previously deselected package libapache2-mod-php5.
Unpacking libapache2-mod-php5 (from .../libapache2-mod-php5_5.3.3-7+squeeze8_armel.deb) ...
Selecting previously deselected package php5-cli.
Unpacking php5-cli (from .../php5-cli_5.3.3-7+squeeze8_armel.deb) ...
Selecting previously deselected package php-pear.
Unpacking php-pear (from .../php-pear_5.3.3-7+squeeze8_all.deb) ...
Selecting previously deselected package php5-cgi.
Unpacking php5-cgi (from .../php5-cgi_5.3.3-7+squeeze8_armel.deb) ...
Selecting previously deselected package php5.
Unpacking php5 (from .../php5_5.3.3-7+squeeze8_all.deb) ...
Selecting previously deselected package php5-suhosin.
Unpacking php5-suhosin (from .../php5-suhosin_0.9.32.1-1_armel.deb) ...
Selecting previously deselected package sgml-base.
Unpacking sgml-base (from .../sgml-base_1.26+nmu1_all.deb) ...
Selecting previously deselected package xml-core.
Unpacking xml-core (from .../archives/xml-core_0.13_all.deb) ...
Processing triggers for man-db ...
Setting up libxml2 (2.7.8.dfsg-2+squeeze3) ...
Setting up ucf (3.0025+nmu1) ...
Setting up libonig2 (5.9.1-1) ...
Setting up libqdbm14 (1.8.77-4) ...
Setting up php5-common (5.3.3-7+squeeze8) ...
Setting up libapache2-mod-php5 (5.3.3-7+squeeze8) ...

Creating config file /etc/php5/apache2/php.ini with new version
Reloading web server config: apache2apache2: apr_sockaddr_info_get() failed for meckk
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for ServerName
.
Setting up php5-cli (5.3.3-7+squeeze8) ...

Creating config file /etc/php5/cli/php.ini with new version
update-alternatives: using /usr/bin/php5 to provide /usr/bin/php (php) in auto mode.
Setting up php-pear (5.3.3-7+squeeze8) ...
Setting up php5-cgi (5.3.3-7+squeeze8) ...

Creating config file /etc/php5/cgi/php.ini with new version
update-alternatives: using /usr/bin/php5-cgi to provide /usr/bin/php-cgi (php-cgi) in auto mode.
update-alternatives: using /usr/lib/cgi-bin/php5 to provide /usr/lib/cgi-bin/php (php-cgi-bin) in auto mode.
Setting up php5 (5.3.3-7+squeeze8) ...
Setting up php5-suhosin (0.9.32.1-1) ...
Setting up sgml-base (1.26+nmu1) ...
Setting up xml-core (0.13) ...

root@meckk:~#


root@meckk:~# vi /etc/apache2/mods-enabled/mime.conf 

途中省略

#
# AddHandler allows you to map certain file extensions to "handlers":
# actions unrelated to filetype. These can be either built into the server
# or added with the Action directive (see below)
#
# To use CGI scripts outside of ScriptAliased directories:
# (You will also need to add "ExecCGI" to the "Options" directive.)
#
AddHandler cgi-script .cgi .pl

AddHandler php5-script .php		この部分を追加


設定を反映させます

root@meckk:~# /etc/init.d/apache2 restart 


以下のスクリプトファイル(phpinfo.php)を作成してアップロードします。
<?php
phpinfo();
?>

以下のような画面を確認する事ができます。(一部のみ表示)