[TYPO3] No 'insert/modify acronym or abbreviation' button in htmlArea RTE in IE 7??

[Bing Du]

Hi,

typo3 4.0.6
htmlArea RTE 1.4.4

How come I can see the 'Insert/Modify Acronym or Abbreviation' button in
the htmlArea RTE in Firefox, but it doesn't exist when I open the htmlArea
RTE in IE 7????  It's the same typo3 server, same site and same
configuration.  Anybody else seeing the same problem?

Bing