Why doesn't my Macbook Pro lock right after I put it to sleep?

[SnowLeopard OSX]

I have my Macbook Pro hooked up to a Thunderbolt display.

Basically, when I select "sleep" in the Apple menu, the screen goes black. However, if I click a key on my external keyboard 1, 2, or even 3 minutes later, the computer "wakes back up" without requiring a password.

Why is this? And what's the solution to correcting this problem?

 

[MagicBoy]

Not sure why that's happening, but I'll suggest a couple of workarounds :
1) Use a hot corner to sleep the display (System Preferences/Mission Control)
2) Run Keychain Access then open the Preferences. Tick "Show Keychain status in menu bar". It adds a padlock symbol, which you can click to lock the screen.

 

[DeltaMac]

Maybe you just need to change your settings:
System Preferences/Security & Privacy pane, General tab.
"Require Password for Sleep & Screensaver", and you can adjust the time to "Immediately" if that's what you want.

Apple has that time period as an option, so some folks don't get annoyed because they have to authenticate after accidentally putting their system to sleep.

 

[LewisChapman]

Do you have a bluetooth keyboard & trackpad/mouse connected?