It may be because the desire is a high density or greater pixels per inch, device. Check this page from the android developers guide on developing for different screen sizes: http://developer.android.com/guide/practices/screens_support.html
The part there that talks about dips is important, I've pasted it below.
Density-independent pixel (dip)
A virtual pixel unit that applications can use in defining their UI, to express layout dimensions or position in a density-independent way.
The density-independent pixel is equivalent to one physical pixel on a 160 dpi screen, the baseline density assumed by the platform (as described later in this document). At run time, the platform transparently handles any scaling of the dip units needed, based on the actual density of the screen in use. The conversion of dip units to screen pixels is simple: pixels = dips * (density / 160). For example, on 240 dpi screen, 1 dip would equal 1.5 physical pixels. Using dip units to define your application's UI is highly recommended, as a way of ensuring proper display of your UI on different screens.
Range of Screens Supported