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Be sure to include the full context when asking a question. 
Without more context, to me has to be seriously qualified means that many conditions and/or limitations have to be added to what has been said before it becomes a truly accurate statement.
For example, if someone says, "Eating cheesecake will make you fat", you can respond that you think that the statement has to be seriously qualified, because it depends on how much cheesecake you eat, what kind of cheesecake it is (It may be fat-free cheesecake), and various other factors.
CJ
Edit: I wrote this before seeing your last post. It turns out that this is the meaning I had in mind.