You can work around this limitation by connecting to the network share by mounting it on your system, rather than connecting to it in Nautilus. (It will then still be accessible in Nautilus, as a drive, and it will appear as a drive in other applications too, including other applications that don't display Nautilus's gvfs mounts.)
One way to do this, assuming these are Samba (SMB/CIFS) shares (i.e., Windows or Windows-style shares, including the default way to share folders on an Ubuntu system over a network), is to use smbmount. For example, to mount a network share called foo on a computer called 192.168.1.100, logging in to that machine as the user ek, you can first create a mount point for it by opening a Terminal (Ctrl+Alt+T):
sudo mkdir /media/foo
And then, when you want to connect t it, mount the share:
sudo smbmount //192.168.1.100/foo /media/foo -o user=ek
When you run commands with sudo and you see [sudo] password for user32762: (assuming user32762 is your username on the Ubuntu machine from which you are connecting), you should put in user32762's password for the local machine (i.e., the machine you're connecting from). But after running sudo smbmount ..., you'll also (or perhaps only) be asked for a password, and that's ek's password on the remote machine (i.e., the machine you're connecting to).
With the share mounted in this way, you can access its contents from any application (just browse to /media/foo).
When you're done using the share, you should unmount it:
sudo umount /media/foo