No hun it doesn't seem odd. My nephew who has just turned 4 absolutley loves to come and play with Darcy's dolls and prams/highchair/bed etc - yet his father won't allow him any toys like this - which I think is absolutly dumb. You can get ones that aren't pink and girly either. There's heaps of cool (and reasonably cheap) dollies out there. Darcy has one that cries and laughs at the moment - so real it even sounds like her and I know it didn't cost much.
I think it's a top idea!