Thank you for your inputs canuck_in_uk and Rsquare
We did not live together before that. I am not worried actually with the maiden name but she is. And we got married here, so I guess that would not be much of an issue. We just need to provide proof to support our relationship because we don't have a child yet and we didn't live together prior to my PR status and our wedding. We've been together for 4years+ before I moved here.
I have actually filled up most of the application forms for the sponsor, the bulk of it I guess is on my wife's part. I will tell her to not worry about her having a maiden name in the application.