microsoft equation 2004:mac...... help needed

i am using office 2004:mac........ i was needed to write equations in the word document but when i went to insert > add object > ......... i didnt find microsoft equations there......
what can be the possible reason.......
suggest me something

Make sure you have the Equation Editor installed. If you can't find the Equation Editor, you may have to reinstall it from the Office CD.

Also, you may need to have someone at Apple look at your period (.) key. It seems to be repeating excessively.