Redstone Pulse Problems

So I need to make this program for something but I need it to give a redstone pulse for a shor time then it sleeps. The problem with that is that it will keep the pulse there but it will never release the pulse or go back to false.

Code:

while true do
redstone.setOutput("bottom", true)
sleep(2)
redstone.setOutput("bottom", false)
sleep(2)
end

The code looks ok to me. Is anything else in the area that could be supplying a redstone signal to that line…?

Or are you playing on a server with bukkit/mcpc+? Those have some weird problems with computers and redstone…