The lower division side were victorious against Premier League newcomers Ipswich Town.
As the latter rested players, they were beaten 4-2 on penalties after a 2-2 draw in normal time.
“I think it is probably the highlight so far I would say,” said Jackson, who played alongside Ipswich boss Kieran McKenna at Tottenham.
“Certainly one of them anyway.
“That is the third time coming up against Kieran as a manager and it has not gone great for me in the previous couple.
“So to win tonight against such a talented young coach is nice on a personal level and I am just really pleased for the football club to have a night like this.
“For us as a football club to have a night like this, beating a Premier League team, it is outstanding.
“Obviously my old striker (Ali Al-Hamadi) popping up with a goal after three minutes, you think oh hell, you knew that was going to happen.
“For 15 to 20 minutes they had their way with us and I was a little bit concerned that the game might get away from us.”