I'm not really sure what your question is, but I regularly go back and forth from my mac and my n900 with the following commands:

ssh
scp
sshfs

For sshfs, I use MacFuse and MacFusion on Snow Leapord. If you wish to do the same, you'll have to fix things by following these instructions.

And in case you didn't already know, when you're doing any of the above commands to your n900, you're always logging in as root.