Seam-gen saves your defaults in the build.properties (Ant of course) file inside the [Seam dist]/seam-gen folder.
If like me you have accidentally typed the wrong directory for your project workspace or the wrong directory for your db driver jar file, simply edit the build.properties and the defaults will change.
Seam-gen is a cool part of JBoss Seam. From the Seam docs,
"This is the easy way to get your feet wet with Seam, and gives you some ammunition for next time you find yourself trapped in an elevator with one of those tedious Ruby guys ranting about how great and wonderful his new toy is for building totally trivial applications that put things in databases."
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