UCS2 long message hangs modem

[Wortoll]

When changing the character set in the GSM_SMS.cpp file by adding MODEM.send("AT+CSCS=\"UCS2\""); right under GSM_SMS::available(). I receive all messages in UCS2.
This gets translated and solves issues with accented characters or emoticons... documented in #101

When I now send a message with a lot of characters (somewhere over 140) the modem hangs.

If I then remove the MODEM.send("AT+CSCS=\"UCS2\""); to normal modem.send configuration & upload and reboot, this gets received in 2 messages (ok!)

Is it possible to make the modem 'not hang' ?

Could someone help? This destroys everything I was working on :(

[Wortoll]

FYI
So far I managed to 'trace' this to

int GSM_SMS::ready()
{
  int ready = MODEM.ready();
  TRACE();  //Prints this

  if (ready == 0) { TRACE(); //Prints this  ////// HERE !!!
    return 0; 
  }

  TRACE(); //does not print this
...

Which shows me the way to

int ModemClass::ready()
{
  poll(); //TRACE();

  return _ready;
}

And to: void ModemClass::poll()
Where _ready stays 0 ...

Printing _buffer gives: AT+CMGL="REC UNREAD"

[Wortoll]

FYI
It seems that the order of multiple-messages is sometimes wrong
But the timestamp is correct

My sketch checks if the next message (within a time window) has same number so it can stitch it together.
Now the order is sometimes wrong. I should order them according to time received.

+CMGL: 23,"REC UNREAD","+telnumber",,"20/07/30,21:58:13+08"
0041006100610061006100610061006100610061006100610061006100610061006100610061006100410061006100610061006100610061006100610061006100610061006100610061006100610061004100610061006100610061006100610061006100610061006100610061006100610061006100610041006100610061006100610061

+CMGL: 24,"REC UNREAD","+telnumber",,"20/07/30,21:58:15+08"
00610061006100610061006100410061006100610061006100610061006100610061006100610061006100610061006100610061D83DDE26

+CMGL: 25,"REC UNREAD","+telnumber",,"20/07/30,21:58:14+08"
0061006100610061006100610061006100610061006100610061004100610061006100610061006100610061006100610061006100610061006100610031003000300041006100610061006100610061006100610061006100610061006100610061006100610061006100410061006100610061006100610061006100610061006100610061