Okay, I did some research.
In "Coming to America", the line is:
"No. Do not alert him to my presence. I shall deal with him myself."
In "Return of the Jedi", the line is:
"No. Leave them to me. I will deal with them myself."
Vader says this in the scene where Han is trying to get security...
I thought the line was "Leave it to me, I will deal with it myself", and Darth Vader said it in ANH in reference to Obi Wan's presence on the Death Star.