I am not aware of a date of birth actually being on an airline ticket. The your DOB is in the PNR (personal name record) - i.e., the record of your flight reservation, fare calculation, ticket number, credit card number, phone number, mailing address, etc which is typically visible only to the airline agents. It is not likely that they will cross check all of this with your passport when you check in. Even if it is, you can easily explain the reversal of day and month. This actually happens more often than one may think, because there are cultural differences in different countries as to which comes first.