Initially in the manifest when i don’t set any theme inside the activity tag my option menu look like this which is default..
But once i set this theme android:theme="@android:style/Theme.NoTitleBar" in the activity tag of my manifest file the option menu style changes.
Screen shots after adding android:theme="@android:style/Theme.Holo.NoActionBar.Fullscreen"

Why this happen.
Try this.
Look Here For Android Holo themes with backwards compatibility
Edit Try
android:showAsAction="ifRoom"in menu.xml file. Look at this for More