Dead giveaway for a Brit...
Have you had the car a while and this is a new phenomenon? Or have you recently acquired the car and you have 'always' noticed it?
Also, you did not mention whether you have central locking and whether you are referring to unlocking the boot centrally.
If the last (and you have a central locking problem), then you may not be aware that the boot lock has two key positions. The beautyof these old models is that you can deadlock the boot such that even if someone breaks into the car and opens the doors from inside, the boot stays locked. This feature has gone (at least on my 2001 CLK Cab).
DAS
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