Getting a Cairo context

["Sergei Naumov" <vomus rambler ru>]

Hi!
I am developing a program that has to draw some data using Cairo. The question I have is about getting a cairo context from outside of the signal "draw" that the examples describe. I have a multithreaded application where one thread sets up the GTK drawing area, axes, tickmarks, etc. and another thread has to draw in this area. I attach a function  to a "draw" signal on this GTK widget (drawing area) in one thread, but what do I do in another?  

Thanks in advance,

-- Sergei