I have a very strange problem with Photoshop. I can not use any of the tools, since the cursor appears 'locked'. If I select v on my keyboard, it goes to the zoom tool, but the cursor does not change. If I select the paintbrush tool, I can only paint if I hold down the option key.

This is what the cursor look like (I had to paint it since I couldn't capture it). It is a rectangle with two lines through it.

I am running Photoshop CS4 on a Macbook Pro with Mac OS X 10.6.6. Using both the trackpad and an external Logitech MX5000 mouse I see the same issue.

This started when I fired up Photoshop today for the first time in a while. I can't remember changing any options or doing anything that could cause this.

Is it possible that the option key is somehow locked in place, or there is some equivalent of num lock on? Very strange problem, I would appreciate any help anybody can offer.

Edit: To add, the icon remains the same within all the menu options - it never goes back to being just a normal mouse cursor. Also, right click works fine, and if I hold down option, the cursor goes back to normal and I can paint with it. I can't use Marquee, Lasso, Crop, Type etc. even with option held down.

When I go into Bridge, it is the same icon.