I begrudgingly made a cake filled with icing and a layer of fresh strawberries. I say begrudgingly because I don't normally put fruit or fruit filling in my cakes, just regular icing. I had a small worry that I would wake up this morning and see pink juice seeping through the icing. I was pretty close to right. There were two spots where a small amount of pink juice had seeped out around the border, onto the cake board. Luckily this woman had requested a whipped icing (also something I don't normally use), and I could easily fix it.

How do you avoid this? Do you think it would have happened with regular buttercream?

I have had this same problem myself. First: did you make a "dam" and was it deep enough? One thing I learned and have tried with success is to make a dam with stiffer icing. I would take a small amount of icing and add more powdered sugar. Almost to the point where is was almost crumbly. Once I would pipe that around the edge of the cake I would gently press it down so that it was "stuck" to the cake. Second: after making the dam, I would spread a really thin layer of frosting onto the bottom cake. This sort of helped to trap any juices that escape the from the fruit. and Third: I don't decorate with whipped cream frosting, only on cupcakes. I tell my clients that it doesn't hold up with decorating and color adding. This mainly comes from the fact that I have not found a really good stable whipped cream frosting and I'm not sure how it would effect a fondant covering.
I'm glad that it was an easy fix for you!!

Thanks. I never do whipped icing on cakes unless someone BEGS me to do it. I don't like it because I can't get it smooth like buttercream.

I did try to make a dome around the edge, but I think maybe I put some of the strawberries to close to edge. I probably won't do this again, but if I do, I will try your trick of putting some icing over the top of the strawberries. That might seal it in better.

This whole thing has made me even more glad I don't put fruit fillings in cake! LOL

I have used fresh strawberries several times and haven't had any problems. The trick is to decorate your cake the night before or the morning of delivery and make sure you slice your berries and lay them on paper towels top and bottom to absorb most of the juice before adding to your cake. I put a layer of vanilla mousse and top with the sliced berries. Once sliced strawberries get mushy quickly so they are good for a day or two inside a cake.