> It may not be significant as far as the RFC goes, but it IS a
> significant indicator of spam.

My private spam filter is based almost entirely on the subject line and has somewhere around 2,500 expressions, so I am very familiar with the excessive spacing of spam messages. But it doesn't take the form of leading or trailing white space, and you seldom see multiple contiguous spaces, which is the subject of this thread. What you see a lot of is:

U N I V E R S I T Y D I P L O M A S

and the like. It's a lot of spaces, but not contiguous.

  Eric