[Hampshire] dhcp for wireless and static ethernet on Ubuntu

Hi,

For a long time I've used the wonderful network manager for pain-free
easy networking with Ubuntu.

I've recently been given a static IP address for our LAN here at our
dept. at the university, this is because I was being assigned an
address/gateway/dns via the unveristy's dhcp server which was fine,
but recently the university's dhcp assigned gateway has been dropping
packets etc.. and is generally a long way around to get to servers and
other machines in my office.

I use a laptop which I like to take to and from work every day. At
home I use a wireless router which assigns addresses via DHCP. I don't
use any clever security or anything, I just lock things down on MAC
addresses (my home address not disclosed!) I may change this in the
future of course!

So anyway, I had a go at trying to get my ethernet work connection to
use a static IP by adding a static IP via the the
system/network/interfaces gnome menu thing. This sort of worked,
network manager went a bit crazy so I had to disable that, then it
worked fine, or so it seemed. Once I got home, something very weird
happened, I couldn't SSH into any machines at my office, but I could
access the rest of the internet. This isn't very useful as I also work
at home.

Ultimately, what I'd like to do is get rid of networkmanager (or find
a version that supports static IPs etc) and just use the old non-gnome
/etc/network/interfaces file as that seems to make the most sense to
me. I'd also like for one interface not to intefere with the other
when it's not in use.

Does anyone use their laptop in a similar way, or know what I should
do? I'd quite like to keep networkmanager on my system for times when
I want to quickly access a wireless network.

Thanks,
John.