Just wanted to add some info...
I was reading this books " cine mini kaburlu" by Aarudra. He talked about
making Aah at a time in three languages, Hindi, telugu and tamil. The songs were also recorded at a time in Mumbai. Aarudra went for the recordings with SJ. He says that Mukesh and Lata sang in telugu !! But that Raj Kapoor, the perfectionist sent them for evaluations and found that they are not up the mark...and on suggestions by Aarudra made AM Raja and Jikki sing the songs. It would be wonderful to hear Mukesh sing in Telugu !
Aarudra even said that Lata got miffed at this decision to change her..and proclaimed to Aarudra that one day she will do a concert in South and get their approvals too ! Aarudra says that she could have done, given her hardworking nature..if not for the fact that she got too busy ..