I might be misunderstanding the question, but it sounds like you asking if you can assign $hash{'key'} = "something"; and then later assign  $hash{'key'} = "something_else";

This is not possible. You could put it in an array if it already exists, like $hash{'key'} = ( exists $hash{'key'} ) ? [ $hash{'key'}, "more" ] : "else"; but then you have to test each value before you use it. Unless, you just always put it in an array, ie $hash{'key'} = ( exists $hash{'key'} ) ? [ $hash{'key'}, "more" ] : ["else"];

Hope that wasn't too far off from the question...

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