Ashlee Simpson is excitedly preparing for her 21st birthday - because she'll no longer have to pretend to be her older sister JESSICA whenever she wants to gamble.

The PIECES OF ME singer, who celebrates her big day on 3 October (05), is counting down the days until her birthday arrives, because she can't handle the embarrassment of getting caught out for using identification cards not belonging to her.

She says, "I go to (Las) Vegas a lot, sometimes with my family and stuff, and I'll try to do the coin machine. But somebody always taps me and says, 'Can I see your ID?'

"I used to use my sister's ID, which is really lame. They were like, 'Jessica Simpson... You're Jessica Simpson?' And then I used to have one that said, 'Luanne'.

"But then there came a point where people were like, 'You're not 21 and I know that.' So I can't go to those places. But I almost am (21)."

While reaching the milestone will allow her to drink alcohol legally, Simpson is more thrilled by the idea of gambling.

She notes, "People drink like in high school and stuff, but you can't gamble... I don't even know how to play (poker). I don't even care about gambling. I just want somebody to tap me on my shoulder and say, 'Can I see your ID?'"