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not an issue. Just make sure that you maintain his same name througout the application and the supporting documents.

His PR will be issued in that name. If he wants to carry your husband's last name in future, it's best to have his last name as your husband's last name.
 
Dear Ms Meena,
Dont change any names...
You should mention in the Form that you are also known as Meena Khan even if your passport has Meena Umar.

One more thing, I hope you have your spouse's name inserted on your passport and vice versa. If not just do this. This will take a day or two (Make sure if your passport has Meena Umar as your name , your spouse should get Meena Umar inserted on his passport as spouse name and not Meena Khan)

Rest is no issue.
I had the same situation....and never faced any problems.