in the MySQL doentation up to version 5.1 the page "Data Types ->
.... -> TIMESTAMP Properties as of MySQL 4.1" states:
"It is not possible to have the current timestamp be the default value
for one column and the auto-update value for another column."

Is this a bug or a feature?

I mean... in many applications you need to track when an entry is
created and when it was last changed. I'm wondering why this is not
implemented, since it is such an important feature. And in 4.1 the
TIMESTAMP-type has been worked over, that would have been a chance to
implement it.

Is there any reason against it?