I also wondered how you got this comment box with intensedebate.
I tried to insert it via the basic installation but when clicked on the comment link on my tumblr it would just show the post notes. Also tried it with the advanced intallationa and no joy.
I was thinking how you did it as you have the same theme as me.

Any help would be really appreciated when you get a spare moment.

yep it is, lavernepereira.tumblr.com :OS