I searched a solution to handle the sending of big SMS on Android. The solution appears to be to use the following method:
ArrayList<String> parts =smsManager.divideMessage(sms_content);
smsManager.sendMultipartTextMessage(recipient.contact_phone, null, parts, sentIntents, deliveryIntents);
If the received SMS message is correctly formated (only one big message), in my outbox I get multiple messages. Anyone has the clue of this?