Arithmetic error in Feller's Introduction to Probability? In my copy of An Introduction to Probability by William Feller (3rd ed, v.1), section I.2(b) begins as follows:

(b) Random placement of r balls in n cells. The more general case of [counting the number of ways to put] $r$ balls in $n$ cells can be studied in the same manner, except that the number of possible arrangements increases rapidly with $r$ and $n$.  For $r=4$ balls in $n=3$ cells, the sample space contains already 64 points ...

This statement seems incorrect to me.  I think there are $3^4 = 81$ ways to put 4 balls in 3 cells; you have to choose one of the three cells for each of the four balls.  Feller's answer of 64 seems to come from $4^3$.  It's clear that one of us has made a very simple mistake.
Who's right, me or Feller?  I find it hard to believe the third edition of a universally-respected textbook contains such a simple mistake, on page 10 no less.  Other possible explanations include:
(1) My copy, a cheap-o international student edition, is prone to such errors and the domestic printings don't contain this mistake.
(2) I'm misunderstanding the problem Feller was examining.

Assume sampling with replacement, there are four possible balls for cell 1, four possible balls for cell 2, and four possible balls for cell 3. So there are 4^3=64 possibilities.
(Assuming sampling without replacement, there are four possible balls for cell 1, three for cell 2, and two for cell 3, for a total of 4*3*2=24.)
So it seems the original Feller was correct.
