如何在 Ubuntu 8.04 上安装 PHP5.3 和 SQLite3

我有一个 Ubuntu Hardy VPS，我正在尝试使用 SQLite 安装 PHP5.3。我添加了dotdeb PHP5.3存储库并成功安装了PHP5.3。但我也需要安装 SQLite。当我尝试安装 php5-sqlite3 ( sudo aptitude install php5-sqlite3) 时，输出如下：

The following packages are BROKEN:
  php5-sqlite3 
The following NEW packages will be automatically installed:
  php-db php-pear php-sqlite3 
The following NEW packages will be installed:
  php-db php-pear php-sqlite3 
0 packages upgraded, 4 newly installed, 0 to remove and 0 not upgraded.
Need to get 460kB of archives. After unpacking 3027kB will be used.
The following packages have unmet dependencies:
  php5-sqlite3: Depends: phpapi-20060613 which is a virtual package.
Resolving dependencies...
The following actions will resolve these dependencies:

Remove the following packages:
libapache2-mod-php5
php5
php5-mysql

Install the following packages:
php-pear [5.2.4-2ubuntu5.10 (hardy-updates, hardy-security)]

Downgrade the following packages:
php5-cli [5.3.1-0.dotdeb.1 (<NULL>, now) -> 5.2.4-2ubuntu5.10 (hardy-updates, hardy-security)]
php5-common [5.3.1-0.dotdeb.1 (<NULL>, now) -> 5.2.4-2ubuntu5.10 (hardy-updates, hardy-security)]
php5-suhosin [5.3.1-0.dotdeb.1 (<NULL>, now) -> 0.9.22-1 (hardy)]

Score is 197

Accept this solution? [Y/n/q/?]

显然，降级 PHP 不是一种选择。

请帮我！如果将服务器升级到更新版本的 Ubuntu 会使事情变得更容易，那不是问题。