Calvin Hsia's phonebook solution

[KoenPiller]

Hi,

I am puzzled with Calvin's solution to transform a given phonenumber into a word / sentence. Obviously I have already questionned him but most probably to other urgent dealings no reply.
How did he fix it?
How did he squeeze a 225'000 words into 679K DLL ? and how does this line

 IF !SEEK(LEFT(cNumber,nDigNum)+' ',"SubWords",2) and ox.isword(LEFT(cNumber,nDigNum))

work?
The full listing can be read in his blog:

http://blogs.msdn.com/vsdata/archive/2004/04/05/107986.aspx

If somebody else could give me some clue I would like to know.

Koen