I've just tested the Input sample with the simulated 520 using the 3.0.7 SDK.. Pressing the top-right button does indeed generate a KEY_ENTER event with a ON_SELECT behavior as expected.
You mention this is a problem with a menu. Since the e520 doesn't support Menu2, it's just Menu. You push the menu view, and then up/down buttons allow you to highlight an item, and then a short press of the upper right button selects it. Are you trying to use the button on the bottom to select the item? Try Hike2. There, a long press of the upper right button displays a menu, and a short press selects it. The right button on the bottom starts/stops recording, and when you stop recording, there is also a resume/save/discard menu. It's working fine on both the device and in the 3.0.7 sim.
Maybe post the code for when you push the menu, and the menu's delegate.
I've just tested the Input sample with the simulated 520 using the 3.0.7 SDK.. Pressing the top-right button does indeed generate a KEY_ENTER event with a ON_SELECT behavior as expected.
In the sim with the Input example, it's KEY_MENU and ON_MENU