Here is the latest result (
Here are some information given by the supplier about the issues:
1) http://forum.xda-developers.com/archive/index.php/t-557641.html
2) http://androidcommunity.com/forums/archive/index.php/t-21243.html
3) http://androidforums.com/motorola-milestone/48385-seidio-extended-life-battery.html
He also mentioned: 'I think what you need to do is completely discharge the battery and then do a full continuous recharge maybe three or four times so that the phone can adjust to the new higher capacity so it knows how much it can recharge before stopping. i remember having to do a similar thing with laptops when you increase the battery size.'