Can I have multiple GOPATH directories?

I set my GOPATH to

/Users/me/dev/go

and I have

/Users/me/dev/go/src/client1
/Users/me/dev/go/src/client2
/Users/me/dev/go/src/client3

and also

/Users/me/dev/client1/rails_project
/Users/me/dev/client2/php_project
etc.

I don't like how in my root dev folder I'm forced to have this general "go" dir that holds many different client's go projects.