Shadows on water shader

I have a water shader that works fine, but the only thing i´m missing is the shadows, it doesn't look too bad without them but it would look beter if there were shadows. Is it possible to render them on a water shader with Unity?

 

If it's a surface shader adding "addshadow" to the end of your pragma will work.

Like this:

Code (CSharp):

1. #pragma surface surf BlinnPhong vertex:vert addshadow

 

I'm using a fragment shader, so that doesn't work.

 

Maybe try here: http://answers.unity3d.com/questions/180298/how-do-i-sample-a-shadowmap-in-a-custom-shader.html