According to the project page on Source Forge, the DBD module is part of the down-load.To quote the Fine Article:

The SQL Relay client API's support advanced database operations such a
+s bind variables, multi-row fetches, client-side result set caching a
+nd suspended transactions. SQL Relay has native client API's for the 
+following languages:

    * C
    * C++
    * Perl
    * Python
    * PHP
    * Ruby
    * Java
    * TCL
    * Zope

SQL Relay provides drivers for the following database abstraction laye
+rs:

    * Perl DBD
    * Python DB
    * Ruby DBD
    * PHP Pear DB

<snippage>

For questions about SQL Relay or other firstworks projects please mess
+age: dmuse@firstworks.com.
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