virtualbox.org

I have installed solaris 10 as guest on my windows vista and wanted to
access shared folder on my host (vista) form guest. But i read in user
manual that Shared folders are not yet supported with Solaris guests

user manual version Version 2.0.4 page : 181

Is there any way to do this?

If you can access normal network shares from Solaris with software like Samba, you can create a normal share and connect to your Host's share that way. If you use NAT, your Host is accessible on 10.0.2.2.