Activation link doesn't activate new password

Hi, i newbie and have a problem with "forget your password" function.

When i enter email adress of my account, system send email with new password and activation link, but activation link only redirect back to my pages and new password doesn’t activate. Old password is still active.

Thanks for yours advices.

I use modx 1.0.2

I found when replace & in activation link with & symbol, new password is sucessfuly activate. So why activation link is generated with &

Wrong modx generated activation link:
http://sitename/index.php?id=1&webloginmode=actp&wli=2&wlk=NMf6FhtZ

Correct link:
http://sitename/index.php?id=1&webloginmode=actp&wli=2&wlk=NMf6FhtZ

Fixed disable Replaces ampersand in system config.

Replaces ampersand (&amp;) characters in urls that are generated by MODx with the validating &amp;<!-- -->amp; htmlentity’;