Zac Efron’s Australian Mystery Blonde

Is Zac Efron and Vanessa Hudgens’ relationship heading for Splitsville?

High School Musical heartthrob Efron, 21, is in Australia to promote his new movie, 17 Again, and while in Sydney he decided to see the sights with an unknown female companion.

Who, being unknown—and also being blonde—is definitely not Vanessa Hudgens.

This comes on the heels of Hudgens’ rep admitting that Efron and Vanessa are not living together, and not planning on getting married anytime soon.

And, of course, Efron was recently spotted roaming around Los Angeles with Friday the 13th hottie Danielle Panabaker.

And now…this.

Sure, Efron’s mystery blonde could be a publicist. Or reporter. Or condom procurer.

Or not.

Readers, have your say in the comments section: Is Zac and Vanessa’s relationship smooth sailing, or heading for an iceberg?