TOPIC Solved: Answer below.
Some users have been reporting border alignment issues on some android components such as the alert popup or the editTexts. This is happening on the Samsung Galaxy Apollo (200x400) and the HTC Pro Touch (480x640) devices. I cannot replicate that because i don't own those devices and in the Samsung Galaxy S and emulator everything looks just right.
I think that the problem is the dpi or resolution of the device (because the edittext background is a single .9.png so image should look ok); however I am not sure if the supports-screens tag is the solution. Also, application was developed using Api 3 (v1.5) and supports-screens was not yet supported, nor the screen-size resource qualifier.
The style used for the alerts and editText is the phone default. Could the problem be something related with the theme applied to the phone by the user?
Thanks in advance!, I show some images given to me showing the problem: