Nokia, missing 4 in model no

Question

some old models like 1100, 1600,.......etc and new basic phones like 1208, 1209,.........etc
M. Xpress model like 5130, 5610,....etc
Smart phones like 5800, 5235,...etc
Not to mention all n7x, nxx,....etc
And new models like x2, x3, x5, x6
E5x, E6x, Cx....etc, etc
From X3, it jumps to X5, X6
C3 to C5 etc.
I wonder why number 4(four) is missing in most of the models
There are some acc. model with 4 like BH-214 but never seen in phone model no.(am is missing something?)
Not so serious but......
Does anyone know the secret of nokia in hidding number '4' from their model number?

Answer 1

No problem, Here it is a copy of that comment for anyone who can't find it:
Saara wrote October 3rd, 2008 at 10:29 am
As a polite gesture to our Asian customers, we decided move from 3rd Edition directly to 5th Edition. In Asia number 4 means bad luck.
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