Hi sanjeevkmrs,
1) There is a 3rd party solution that will allow you to do this. It's called Bberrysync. You can find it at:
http://store.handango.com/blackberry/PlatformProductDetail.jsp?siteId=1181&osId=1946&platformId=5&productType=2&productId=224782§ionId=6676&catalog=40&topSectionId=65932) Not strictly possible. However, you could set up a forward/redirect from one mailbox to the other so that you can see mail from both addresses on the BlackBerry device.