Ubuntu 9.04: overzealous DHCP client

[Maurizio Vitale]

I switched to DHCP using the Network Manager in order to connect
directly to my ADSL modem and debug a few issues I had.

Upon switching back to static IP assignment (the switching itself works)
I find myself switched back after a few tens of minutes (haven't figured
out if it is on the hour, but I have nothing in my cron.hourly).

Somebody knows who might be the culprit and point me in the right
direction?
Before touching the Network Manager for setting DHCP I've been running
with static assignment since 8.10.

Thanks,

        Maurizio
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