So 'Hacker' writes a program which then starts re-writing itself inexplicably. It becomes conscious. It creates a voice for itself. Authorities are chasing Hacker and his girlfriend all over the city. I don't think the program was evil, just mis-understood. At some point I think the program called Hacker on a payphone. That is all I can remember.
"A hacker...creates an artificial intelligence named P-1, which goes rogue and takes over computers in its desire to survive and seek out its creator..."
As you can see from the (bad) screencap below, the computer creates a voice by listening to the hero's phone calls and sampling them. Although the character's name is Gregory, he's certainly referred to as a "hacker" within the film and there is also a scene where he uses a payphone.
You can view the trailer below.