Why my Serial.print is ambigous?


I am trying to understand a part of the TnyGPS.
Some time,it return the date as, the following


I am looking at this function

void TinyGPS::crack_datetime(int *year, byte *month, byte *day, 
  byte *hour, byte *minute, byte *second, byte *hundredths, unsigned long *age)
  unsigned long date, time;
  get_datetime(&date, &time, age);
  Serial.print(F("DEBUG GPS: date:")); Serial.println(date);
  Serial.print(F("DEBUG GPS: time:")); Serial.println(time);
  //Serial.print(F("DEBUG GPS: age:")); Serial.println(age);
  Serial.print(F("DEBUG GPS: year:")); Serial.println(year);


I am trying to print the year and the age, but when I compile, I got ths error messag

TinyGPS.cpp:382:60: error: call of overloaded 'println(int**)' is ambiguous

Serial.print(F("DEBUG GPS: year:")); Serial.println(&year);

I tried the following:

Serial.print(F("DEBUG GPS: year:")); Serial.println(year,HEX);
Serial.print(F("DEBUG GPS: year:")); Serial.println(year,DEC);

I also thoug to add an & at the year variable.
But none works. And what about the 'age' variable?