In another post you are asking others about the B747-400LR/B747-400ER. Now you are so sure what it is!
By the way, Boeing calls the longer range 744 the 747-400ER.
According to their site, there is only 1
customer for the B747-400ER. It IS Qantas
who have ordered 6
Info correct up to March 2001.
Click on the link. Set the 'Model' field to '747-400' and press search. See the summary table for B747-400ER.
I'm sure Juanchito is asking about the -ER.