IBM recently released JTOpen 3.3, an open source JDBC driver for connecting ColdFusion to DB2/400. Believe it or not, I'm not the only person out there using DB2/400 as a backend database. Anyhow, you can download the latest version from http://oss.software.ibm.com/developerworks/opensource/jt400/downloads.html. Note that registration is required.
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