Is there any documentation, samples, or external projects that show Seam actually working with Acegi?
Reference Documentk doing a search for acegi has no information.
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Forum asking same question forum reference where someone else also asked, but didn't get an answer.
And to answer the question of 'why not use Seam security', it is because other, non-web applications use Acegi and would be nice to use the same security in both thick client and web applications.
Although, I haven't tried it yet. I think it would be similar to setting up ACEGI and JSF, since Seam uses richfaces.
You'll also probably have to set it up so it uses spring.
There's plenty of docs on the net about setting up Acegi and JSF.