sticky element don't stick if there's no specific container height

[wobe]

i'd like to use the sticky element as a sidebar on my blog, but since the container doesn't have a specific height in the css (because that depends on the posts' lenght) the stickyness doesn't work. how can i fix this? thanks!

[tatof]

give the container a float left so the height is "fixed"?
I use it without a container height and it works fine!

Demo: http://devtof.nl/stick/