[TYPO3] rtehtmlarea - new issue or my issue

[Simon Browning]

I've got a typo3 3.8 site we maintain.  We just updated the rtehtmlarea 
to version 1.2.2 to get over the firefox issue, now though we can't add 
images in the rte area.  When we click the image button we get:

Cannot find configuration. This file is probably executed from the wrong 
location.

Getting it in both FF and IE.

I've dumped caches, cleared temp files, removed & deleted, then 
reinstalled the extentions, cleared all js files out of typo3temp, stood 
on my head and run twice around the block.

Any clues?

Thanks.

Simon