math.exp bug on alpha?

[Luigi Ballabio <ballabio@mac.com>]

Greetings,
	on alpha debian, python 2.1.1-8:

>>> import math
>>> math.exp(-720)

aborts the interpreter with a floating point exception. The strange thing 
is, exp(-700) and exp(-750) both work.

Any insight?

Thanks in advance,
		Luigi