My provider does not send NITZ information.

I was looking for a way to synchronize my N900 time with the
DCF77 time from my desktop machine (I use some older parallel port dongle, see also http://de.wikipedia.org/wiki/DCF77 ).

There are only some posts about some older version of "rdate",
about a daemon "openntpd" (I do not want to install a complete
ntp daemon, I only need the client).

Finally I found this website:
http://home.mminternet.com/delaroca/index.html/
where there is:
"Download ntpdate.gz: Ntpdate 4.2.6p1. Home
(Install in your favorite bin/ dir, run in root)".

Installed this and now I can either do (after starting the ntp daemon
on my desktop)
ntpdate <my desktop in my WLAN>
or switch on internet and
ntpdate <public ntp server>

hwclock -w also works.