Bob, it sounds to me as if you may have an underlying problem....is your version of computer one where you can remove the battery, or is the battery built-in and not user accessible?
If the battery is removable, try taking it out while the computer remains connected to external power.....a swollen battery (one of several ways that a battery can fail) can press on the underside of the keyboard and cause that repeating issue.
If the battery is built-n, use the System Profiler to check its' condition.
