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Integration Wizard

The Integration Wizard will generate code for your Express Checkout or Payflow integration:

* Express Checkout
* Express Checkout using Payflow Gateway
* Payflow - credit card processing

IPN/PDT

This is a simple helpful filter module if you want to post colored and formated text in body.
It handles &ltcode&gt&lt/code&gt and &lt?php ?&gt tags so that users can post code without having to worry about
escaping with < and >

Project Link page:-

http://drupal.org/project/codefilter

Related modules/alternatives

* Code filter: a simple module with support for PHP syntax highlighting
* Syntax Highlighter uses a Javascript library to add syntax highlighting client side (unlike GeSHi filter, which renders the highlighted code server side).