A Question for Murray Waas

Murray Waas reports the following in his latest piece in the National Journal:

On September 29, 2003, three days after it became known
that the CIA had asked the Justice Department to investigate
who leaked the name of covert CIA officer Valerie Plame,
columnist Robert Novak telephoned White House senior
adviser Karl Rove to assure Rove that he would protect him
from being harmed by the investigation, according to people
with firsthand knowledge of the federal grand jury testimony
of both men.

Rove testified to the grand jury that during his telephone call
with Novak, the columnist said words to the effect: "You are
not going to get burned" and "I don't give up my sources,"
according to people familiar with his testimony. Rove had been
one of the "two senior administration" officials who had been
sources for the July 14, 2003, column in which Novak outed
Plame as an "agency operative." . . .

Rove, according to attorneys involved in the case, volunteered
the information about the September 29 call during his initial
interview with FBI agents in the fall of 2003.

Compare that to this account from Waas' October 7, 2005 article:

Then there is the matter of the source-reporter relationship
between Rove and Novak. Rove, in giving his assurances to
the president in the fall of 2003, did not say he had served
as a corroborating source for Novak's column about Plame.

Sources close to Rove say he simply did not know at the time
that Novak had used him to corroborate the Plame information
published in the July 14 column. Rove did not discover that
until after his initial interview with the FBI, sources say.

These two accounts seem hard to square with one another. How could Rove not have known that he was one of Novak's sources after Novak went out of his way to call him and assure him that he was "not going to get burned," that he would not "give up [his] sources"? And did Karl have this conversation with the President before or after his conversation with Novak? If after, did Rove lie to the President?

Murray, if your sources for these two articles are the same--which seems likely--can you clarify what the timeline of events is here and how exactly Rove claims to have first learned that he was one of Novak's sources for the original Plame column?