SDS-PAGE with small proteins

[Marcin]

Hi everybody,
I wonder if anyone knows how to separate and visualise small proteins 
(4-10 kDa) on a gel. I tried gradients, high percentage gels and 
Tris-tricine gels w/o any luck. When I stain with Coomassie or Ponceau 
(after transfer onto 0.2 u nitrocellulose) I can see nice bands up from 
10 kDa. Below that point nothing shows up! Also, I tried blotting with 
specific abs w/o any success. I would appreciate any suggestions.
Cheers, Marcin