The game's authorities had feared the worst when the two clubs were paired together over a two-legged semi-final and Millwall claimed some sections of the media had overplayed a small pitch invasion at the end of their 1-0 win in the first leg at The Den on Saturday.
Jimmy Abdou silenced a partisan full house at Elland Road on Thursday night with a 73rd-minute equaliser to clinch Millwall a date at Wembley against either Scunthorpe or MK Dons a week on Sunday as the second leg ended 1-1.
Leeds striker Luciano Becchio had levelled the tie early in the second half, sending most in a crowd of 37,036 into raptures after the disappointment of seeing Jermaine Beckford's penalty saved five minutes earlier.
Jackett was unaware Beckford's penalty had been delayed after a coin had been thrown at Millwall goalkeeper David Forde just before the spot kick.
He said of the 1,000 Millwall fans handed their tickets by Leeds officials at Woolley Edge service station prior to their arrival at the ground: "They've always given the club fantastic support and they did again here.
"Every time it went quiet I could hear them. They've been tremendous all season and we know the passion of the Millwall fans if you're successful.
"It's a big attraction for myself because they make a lot of noise and they back the side. It's a passionate football club."