CS4 lets you set attributes per layer, yes? I'm shooting in the dark here, but I know in CS3 you can disable layer settings... one of them may be editing. Check it and see if thats the case. You can also try HERE. Don't know if it's your exact problem, but there are some good tuts in the links.
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Every time you think you've made it idiot proof, someone comes along and invents a better idiot.
?the end of our exploring, will be to arrive where we started, and know the place for the first time. - T.S. Eliot