How to notify gnome (network manager?) about network connection setup by my own script/tool?

Hi,

I had to integrate the e173-u2 modem working in NDIS mode with Linux.
(As this particular operator has blocked TS11 services in his SIM
cards,
this is the only way to obtain connection).

Unfortunately I was not able to do it in the framework of network
manager
and therefore I've written my own simple tool (sources available in
alt.sources
thread "Public domain sources for NDIS mode dialer for e173 modem",
direct
link in google archive: http://groups.google.com/group/alt.s...099db917b2c33#
)
This solution is currently used in a Debian/testing laptop.

Even though the above script works quite reliably, some programs (e.g.
telepathy)
refuse to connect to the server, probably because they rely on the
information
from network manager (or from Gnome itself?) that no network
connection
is available.

I don't want to deinstall network manager, as sometimes this laptop is
used
in an environment where other, well serviced by the NM connections are
available.

Therefore I think, that the best solution would be to allow my script
to notify the NM
or the Gnome about connection to the network and/or disconnection from
the network.
Could someone please provide me with any hints?
Probably I should use the python-notify package and send the
"network.connected" and/or
"network.disconnected" notifications, but are there any examples how
to do it correctly?
Thank in advance,
WZab