"I don't want to be another Britney Spears or Christina Aguilera," said Mumba, who hails from Ireland.  "People don't know what to make of me, and that's just fine."

But the 17-year-old Mumba is on the fast track to join Spears and Aguilera on the charts with "Gotta Tell You," which shot to #4 on the "Billboard" Hot 100 this week and is moving its way up the R&B chart.

The song from Mumba's upcoming same-titled debut album is heavy on beats and processed vocals, but Mumba doesn't intend to hide her pipes behind electronic effects.

"I want to make sure my music sounds current, but I want even more to make sure people can identify that it's me," she said from Belfast, Northern Ireland.

Born in Dublin, Mumba garnered a local following by singing in a modern production of Gilbert & Sullivan's "The Mikado," which got her invited to sing on several Irish TV shows.

Mumba, who left school last year after too many bleary-eyed mornings that followed performances, didn't set out to become a professional singer.

"Music chose me," she said.  "I just sang, and all these things happened."  She said she'll return to school if her music career fizzles, which doesn't seem to be in danger of happening anytime soon.

In addition to the hit single, the Gotta Tell You LP includes "Body II Body," a dancefloor remake of David Bowie's "Ashes to Ashes" -- a song recorded three years before Mumba was born.

"That wasn't my idea, but the track is pretty irresistible," Mumba said.  "We didn't expect Bowie to approve it, but he gave us the go-ahead."

In the UK, Mumba is at least as well known for her manager -- Louis Walsh, who handles Boyzone and Westlife -- as she is for her music.  So she's looking forward to testing the waters across the pond, where those acts aren't household names.  "In the US, people aren't as obsessed with pop stars," she said.

With top 10 success in hand on these shores, Mumba now hopes to define herself as a songwriter.  She co-wrote "Gotta Tell You" and the ballad "Never Meant to Be" and said she hopes to write more for her next album.

"I'm not a songwriter yet," Mumba said.  "That's a real craft, and I'm just learning it."