alt hotkey problems

[chlsmith]

For some reason, when I click an ALT-<letter> hotkey combo, it doesn't
actually click the button that I need.

For instance, if I'm in Outlook and create a message, then hit ALT-<s>
to send the message, the Send button is highlighted, but it doesn't
click it. Similarly, if I'm in Word and click ALT-<v>, "View" becomes
highlighted on the top, but the toolbar doesn't drop down.

This doesn't happen in non-MS Office apps. In Acrobat Reader, if I
use the keys, things work as expected.

Any ideas? I don't see anything in my keyboard options to change.

Thanks!

Chris