Permalink Structure with .html after post name

Hi,

I am trying to achieve the URL to look like

http://www.mysite.com/year/month/post_name.html by updating the Permalink Structure.

On my site I have modified the structure to /%year%/%monthnum%/%postname%.html

After this I see that some pages work just fine, but most of pages show bare content text (no theme decorations).

e.g Following page on my site (http://www.indianuncle.com/wp/) looks just fine

http://www.indianuncle.com/wp/2005/10/gulshan-grover-to-act-in-next-james-bond-film.html

BUT post just next to it shows up messed up
http://www.indianuncle.com/wp/2005/10/memory-clinic.html

I have imported this blog from blogger.com, does it has anything to do with this. Permalink Structure without ending .html works just fine.

Any suggestions, help?