time zone problem

Hi everybody,
I'm located in Hong Kong, UTC+8 time zone. When I

select current_timestamp;

gives

now
-------------------------------
2012-01-13 23:56:16.825558+08

However, when I

select current_timestamp at time zone 'UTC+8';
I expect the result is the same as the above one. But the result is

timezone
----------------------------
2012-01-13 07:57:24.407825

How to get the correct timestamp at the time zone I gave?

Thanks in advance