| Yes, I found that too, when I changed the oil on my 2001 748 recently.
They changed the design (why?) around that model year.
The actual filter is not dissimilar to the pic in the Haynes book, except it has the female 14mm hex instead of the "bolt-head".
As I said above, it's a "double operation" with the Allen key. Better to use a 14mm socket rather than an actual Allen key, cos they can be quite tight. | 
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