That shouldn't matter. If you look in settings, under sounds, if it shows a list of options such as text tone, new voicemail, new mail, etc. then it will work. All you have to do is create your own sounds, which must be in the ringtone format (m4r), upload them into iTunes sync your phone and then you can select them on your phone. That's it.
The goods news here is you can finally create your own tones, such as new email, new sms, etc and put them on your iPhone, very easy to do works well and you don't have to spend money for a 10 second sound