When editing a nodeType:

for CCK "ImageField" >> i have got "Lightbox2: imagecache_xxxxx->imagexxxxx in http://xxxxxxx.xxx/admin/content/types/(nodeType)/display/basic

but not with the CCK "IMCE Image", :-(

It would be super cool to do that

My installation:
Drupal 6.17
Content Construction Kit (CCK) 6.x-2.6
IMCE Image 6.x-1.0-beta2
ImageAPI 6.x-1.8
ImageField 6.x-3.3
ImageCache 6.x-2.0-beta10
IMCE 6.x-1.4
Lightbox2 6.x-1.9