In Nokia N9, just like in Symbian phones, you may reply to a call with a text message.
How to do that?1. When a call arrives, select Mute > Headset icon , and edit the message, informing that you
cannot answer the call.
2. To send the message, select Send.
The system, however, does not allow to change the "I will call you later" text permanently out of the box, so you would have to edit it over and over again anytime somoene calls.
There is a walkaround to this problem. The text is stored in localization file in /usr/share/l0n/meegotouch/ .
Note: "l0n" is "L - zero - N"
You will not be able to access the folder from you PC, so an N9 file manager, e.g. FileBox is required.
The file you're looking for is telephony_[countrycode].qm (e.g. telephony_en.qm for English, _fr for French, _hu for Hungarian etc.)
The text chages whenever you change the phone's language.
1. Download the telephony_[countrycode].qm file to your PC desktop. The easiest way to do it is to copy the file from /usr/share/l0n/meegotouch/ to /home/user/MyDocs so you can access it from USB connected PC.
2. Open it with QtLinguist, an app for translating Qt-based applications. The app will not see it initially until you set *.* mask in Open file.
3. Find qtn_call_msg_default_text in the list. Change the message (see screens below).
4. Save changes and copy the file back to N9, and using FileBox copy it to /usr/share/l0n/meegotouch/ (overwrite)
5. Restart the phone.