[TYPO3] captions for images are gone after 3.8.1 -> 4.0.2 upgrade?

[Bing Du]

Hi,

We upgraded our typo3 server from 3.8.1 to 4.0.2.  I noticed the captions
for  the images (Type: Image) disappeared after the upgrade even though
the caption is listed in the Caption box for the image on the backend. 
Anybody know why and how to get captions show up again?

Thanks in advance,

Bing