What is the reason of this?

I have seen that many times an internal page has high PR than home page. What is the reason for that? Why that internal page does not add value to home page to make home page also same PR.

For Ex. I have an internal page with PR5 and my home page is PR4.

http://sunil-gupta.blogspot.com/2008/03/mrtmp-red5-load-balancing.html PR5

http://sunil-gupta.blogspot.com PR4

Please share your thoughts on this.

 

This is because internal page is linked with more quality backlinks .. instead of the one homepage !! This is natural !

 

This is not unusual. Internal pages or subdomains can have higher page rank than main domain or the home page. If the internal web page has good content with excellent crowlability and good and high number of backlinks then it can have higher PR then the home page.

 

I agree, but why this internal page does not add any value to home page or it adds? I am not sure

 

As per my knowledge, high PR internal pages do not add any value to the home page. You will have to get more good backlinks to your home page too if you want to get a high PR to your homepage.