Ethernet shield returning garbage characters

I have tried to expand one of the Ethernet examples so I can receive several characters - e.g. for sending commands to an Arduino over the net. For some reason, the client always recieves the same 27 rubbish characters when I run this program. Is there a buffer I didn’t clear out or am I doing something wrong?
I have tried this with Arduino 15,16 and 17 on Linux.
The serial output shows that the myword array gets the 27 characters as input when the program is started.
I have also tried a different sketch that doesn’t disconnect the client, this shows that it is only when the Arduino starts up that this happens.

#include <Ethernet.h>

// network configuration.  gateway and subnet are optional.
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
byte ip[] = { 192, 168, 1, 170 };
byte gateway[] = { 192, 168, 1, 1 };
byte subnet[] = { 255, 255, 255, 0 };

// telnet defaults to port 23
Server server(23);

char c;
char myword[40];
int i;

void setup()
{
    // initialize the ethernet device
    Ethernet.begin(mac, ip, gateway, subnet);
    Serial.begin(9600); // DEBUG only
    //initArray();
    // start listening for clients
    server.begin();

}

void loop()
{
  Client client = server.available();
  if (client) {
    // an http request ends with a blank line
    boolean current_line_is_blank = true;
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();
        // if we've gotten to the end of the line (received a newline
        // character) and the line is blank, the http request has ended,
        // so we can send a reply
        if (c == '\n' && current_line_is_blank) {
          // output the content
          for (int l = 0; l < sizeof(myword); l++) {
            client.print(myword[l], BYTE);
            Serial.print(myword[l]);
          }
          client.flush();
          i=0;
          initArray();
          client.stop();
          // client.print(sizeof(myword));
          break;
        }
        if (c == '\n') {
          // we're starting a new line
          current_line_is_blank = true;
        } else if (c != '\r') {
          // we've gotten a character on the current line
          myword[i++]=c;
          Serial.print("Storing character\t");
          Serial.print(c);
          Serial.print("\tin array\t");
          Serial.print(i);
          Serial.print("\n");
          current_line_is_blank = false;
        }
      }
    }
    //client.stop();
    //initArray();
    //i=0;
    
  }
  
   //client.stop();
    //initArray();
    //i=0;
}

int initArray() {
for(int n=0;n<40;n++){
      myword[n]=' ';
      Serial.print("Now resetting number:\t");
      Serial.print(n);
      Serial.print("\n");
}
}