Thank you for the comments, but you did not get my problems right.
Of course I know about freewheel diode, power supply and that stuff.
The problem is _not_ coming from the coil.
I use a diode and a different power supply.
The circuit works correctly.
But when I connect 230V AC to the relay contacts, I get the problems. Even without any load for the 230V AC connected.
My idea is that small sparks at switching causes radio interference.
I could believe this, if there were a load like motor or something, but the relay switches _nothing_. Only a few cm of PCB track. Is that enough load to produce sparks?

Hope you understand me right this time, english is not my mother tongue...

Carsten