Use the viewport meta tag to set user-scalable and use specific scale options:
<meta name="viewport" content="user-scalable=false; initial-scale=1.0;maximum-scale:1.0;minimum-scale:1.0" />
For more accurate repro, have 6-12 divs of content that have "float:left;" as part of the style such that they would float around each other given more space (test in Safari for that)
When switching from portrait to landscape, iPhoney zooms in by scaling up instead of respecting the maximum-scale attribute
No scaling such that more divs appear on the screen on a specific horizontal line.
http://www.chunklove.com - look at on iPhone and the iPhoney 1.1.