ssh-agent compatibility

[RBastianini]

I'm writing a command line utility for the Symfony console that would pull code from a few repositories, but it looks like that git when run through gitlib is not querying the running ssh-agent. I have tried forwarding the existing environment when creating a repository using the environment_variables option key (by just passing the SSH_AUTH_SOCK variabe and by passing the whole $_SERVER array) but it still would ask me for my passphrase for every repo I'm trying to fetch. I'm on ubuntu 16.04. Am I doing something wrong?