This came up On the general Star Wars board thread about Vader deflection of Han's blaster bolts :
Darth Editous said:
Look carefully, and you'll see there is a shower of sparks on the doorframe next to Han, suggesting the blaster shots were originally meant to be deflected. It's a quick cut though, so perhaps they decided against it in editing.
DE
It might be a cool addition to actual see that more clearly.