Password Reset: Sorry, that key does not appear to be valid.

Hi,

We've had a few members report a bug with password reset. They're getting the "Sorry, that key does not appear to be valid." I see that this was an issue in WP 2.5 but can't find any references to 2.7

Here is an example of the reset url http://sceno.org/wp-login.php?action=rp&key=wQYHPAi1x8ZsJmbqAZAz

(just incase that might be funky?)

Currently we're running 2.7

Any thoughts as to what might be causing this or where I can look?