Relax Tool Dialog Amount parameter

Hi there,
is there anyone who can tell me what's wrong with this code?

actionMan.executeAction 2077580866 "40136" -- Unwrap UVW: Relax Dialog
$.modifiers[#unwrap_uvw].setRelaxAmount 1.0

I would like to create a button that opens the relax dialog with the parameter set to "1,0" while I'm working with the unwrap editor ...
The listener returns me OK but nothing happens in the dialog ...
except the second time I run the script after manually closing the relax tool dialog ...
very usefull if someone tells me how to close the dialog via script ...

Thanks to anyone who can help ..