The Brazil international left San Siro for Santiago Bernabeu in 2009 but has fallen out of first-team favour under Jose Mourinho, and is now looking for an exit route.
After having a meal with Rossoneri attacker Robinho, the midfielder admitted he was not enjoying his time at the Blancos.
The 30-year-old told Sky Sport 24: "My situation at Real Madrid is an unhappy one - for me and for others."
When asked if he would accept a reduction in wages to return to the San Siro outfit, he responded: "I have already said I'm open to find a solution. In Milan, I had many beautiful moments and still have friends here.
"I [have] already said I'm open to find a solution with Real, and if it's good for me it's good for everyone."
Despite Kaka saying he wants to return to the Serie A side, the club's vice-president Adriano Galliani had revealed earlier on Wednesday evening that a bid was impossible due to salary issues.
But he hinted free agent David Beckham - who has been on loan at San Siro in the past - is a slightly more likely target.
“Kaka is impossible, as his wages are the problem,” Vice-president Galliani said.
“David Beckham is a suggestion. However, I’d say it is 99.9 per cent unlikely to happen.
“Robinho is absolutely confirmed to stay. We will not sell Abate, so Davide Santon will not arrive.
“We have received other offers for our players, but the sensation is that the squad will remain exactly as it is.”