ESP8266 SSID/PWD too long

Hi,
I have an ESP8266 connected to an ARDUINO DUE. The problem is, that when I try to connect to my access point via the example program "MultiSerialMega" uploaded to the DUE and with the following command send via the serial monitor

AT+CWJAP="Was ist gruen u. stinkt n. Fisch","1111111111111111"

I get an "error" as reply. When I shorten the access point's SSID to "Was ist gruen" then the ESP8266 connects. So seems to be a problem with the length (it is more than 64 bytes) of the string. I came to the conclusion that the buffer size of the serial buffer of 64 bytes could be the prolem, so I changed

#define SERIAL_BUFFER_SIZE 64

to

#define SERIAL_BUFFER_SIZE 256

in "RingBuffer.h", restarted the IDE and uploaded "MultiSerialMega" again, but I still get an error when using "AT+CWJAP="Was ist gruen u. stinkt n. Fisch","1111111111111111"".
As I have connected several devices to my access point, it would be nice if I would not have to change the SSID of it! Thanks for the answers in advance!

...it seems that the problem is not the serial buffer as

Serial1.print("AT+CWJAP=\"Was ist gruen u. stinkt n. Fisch\"");
Serial1.flush();
Serial1.println(",\"1111111111111111\"");

doesn't work either!

It seems that the ESP8266 only accepts SSIDs with a max. length of 31 bytes, but mine is 32 bytes long!

A Google search turned up this answer.

According to the documentation of the standard, the length of an SSID should be a maximum of 32 characters (32 octets, normally ASCII letters and digits, though the standard itself doesn't exclude values). Some access point/router firmware versions use null-terminated strings and accept only 31 characters.

...Thanks!