way to make all caps file extension into lower caps & keep other caps

I have noticed that when have used image ingester pro, to download, there does not seem to be any options to make the file extensions in lower caps before downloading. So I have tried to in expression media, but it seems to make all my other letters in my camera original file names in lower caps, so I have to run the batch remname command multiple times to get the file extension in lower caps, without doing it to other letters.

Is there a way to get image ingester to make just the file extension lower caps? or to do this in expression media?

I am on a macbook pro i7 snowleopard 10.6.3, using expression media 1.0.

Sossity Corby