Android ARM vs Android x86 in qmake .pro file

[sedi]

Hi,
in my pro file I use the usual scopes for OS-specific parts (like external libraries):

win32: {
   [doWin32Stuff]
}
android: {
   [doAndroidStuff]
}

win32: {
   [doWin32Stuff]
}
android: {
   [doAndroidStuff]
}

To copy to clipboard, switch view to plain text mode 

How is it possible to react to the targeted processor architecture (ARM vs x86 on Android)?
In .cpp I can use the predefined compiler macros - but what can I do in the .pro file?
(I need to deploy 3rd party libs - prefereably compiled for the right prozessor :-))

Best regards,
Sebastian