xrange() question

[George Trojan]

Why do I get an overflow error here:

 > /usr/bin/python
Python 2.2.2 (#1, Feb 24 2003, 19:13:11)
[GCC 3.2.2 20030222 (Red Hat Linux 3.2.2-4)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
 >>> import sys
 >>> for n, x in zip(range(4), xrange(0, sys.maxint, 2)):
...     print n, x
...
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
OverflowError: integer addition

but not here:

 >>> for n, x in zip(range(8), xrange(0, sys.maxint)):
...     print n, x
...
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7

George