fail to send/receive trackback in wp2.0

Not quite a fresh problem:

I have recently install brand-new wp2 (rather than a tedious upgrade from wp1.5)
everything works like a charm, besides its trackback.
Neither could I ping other blogs with its trackback, nor could I track myself from my old good wp1.5 ….
By googling I have found something that may seem useful,
https://www.ahknight.net/archives/2005/12/28/fixed-wordpress-20-trackback-issue
but wait a second, I didn’t upgrade my wp at all …
so should I or should I not modify the mySQL table as mentioned in above link ??
As I found no official docs regarding this problem, supporting forum is my last bet now.
Did anyone also encounter same problem and solve it ??
If so please help ??