Messenger 7 and internet history

First excuse my english!
I have xp pro sp2 ie6 notebook
I clean every day the temporary files and internet history.... i have a note book and not so much place on my hd!!!
I use for this work dclean, ccleaner or clean disk security.
Before the installation of msn messenger 7.0425 when i clean the internet history the history disapear in ie6! it's classic!!!
Now when i clean the internet history and messenger is running the history seem to disapear. But when i launch a new session of ie6 and click on history then on today i found all the history. I tried all the cleaner, the ie clean and also delete manually today in Local Settings\History i have the same things.
If messenger is not running the clean was done normally.
If someone could explain me why, i would be gratefull.

 

I found why!!!!
With the new messenger they are ads and you connect to rad.msn.com.
And when messenger was open you couldn't clean the history because there is an application using this file. Windows didn't allow the user to clean a file while an application use it. It's not like unix....