animated blur?

Hello guys. Im working on some animation project atm. And i wuld need some help from U blender heads. Im trying to simulate DoF in yafray. I ve tried it with yefray DoF and i dont like that grainy results. So i ve set up nodes with blur so now i get some nice results with blur nodes.

Now i wuld like to simulate distance of focus with it and i dont know how to handle that in animation. I wuld need to handle distance of focus and ammount of blur.

Any help will be greatly appreciated guys. If there is any other method than with blur and if its animatable just tell me.

Just for the record i ve searched the net for 2 days for this tut and i havent found one except for yefray dof wich i dont like.

Tx in advance, ur mate Vandorius

Perhaps try http://wiki.blender.org/index.php/Manual/Compositing_Nodes_Filters#Defocus ?

Thanks man. I ve seen this tut but i didnt know i can handle defocus in DoF anim settings.
I have another question now…Can i handle blur the sam as defocus in anim?