bash - rename files in a loop

Hi,
I need to rename the resulted searched files from a loop

I have the following code:

find . -name DOC* | while read i
do
find $i -type f -name '*.txt'
done

basically, I am searching for all txt files inside any folder starting with DOC name.
this code is working fine with me.
I need to rename those .txt files to .txtOLD

OS: Ubuntu 10.4
Bash shell

how can i do that , appreciate your help
Thank you,

 

that's easier than it looks

just do a

Code:

mv *.txt *.txtOLD