Unexpected result in PHP sunrise

[basil]

I'm using the sunrise function pretty much as per the manual.

PHP Code:
echo "<font size='-4'>".date_sunrise(time(), SUNFUNCS_RET_STRING, -28.0361, 148.5814, 90, 10) ."</font>";
But, the time it returns is 29.13, where actual sunrise is 5.13.

My server is on PST time (GMT -8) and I want sunrise for GMT +10, which is where I am, and where the target audience is

It can be viewed at http://www.maranoa.org.au/xoops/index.php.

My questions are:
how do I fix it?
Some people say they see it OK - as in 5.13. Why is that?
Look forward to your reply.