Mario,
I assume you meant Arduino Analog pin 4, or Arduino pin 18, or AVR pin C4 as there is no port A on the m328.
BTW, since you are using a breadboard and not an Arduino board with labeled pin numbers, you might find the new pin configuration designation capability useful.
You can now specify pins using a PIN_Pb notation in the GLCD library config files as well as using Arduino pin #s. So if you want to specify AVR pin C4 (PORTC bit 4) you can use PIN_C4 rather than 18 or PIN_D2 rather than 2.
It may be my own ludditeness, but I find the Arduino pin numbering scheme a PITA when trying to specify AVR pins or connect
wires to AVRs that are not on labeled Arduino boards or boards like the Teensy that use AVR port&pin designations in their labels.
I'm not a fan of having to use a decoder ring to configure my code
and then again to hook my wires.
--- bill