CAPTCHA For Users

There has been a SERIOUS problem with SPAM on the site lately, the price to pay for being heavily indexed by Google!
 
But the major problem was a few of the register user accounts where spamming the site left, right and centre! So to stop this until I clear out the culprit accounts I have enabled CAPTCHA on user accounts too. (Sorry!)
 
Also I have had to make the CAPTCHA challenge a bit more aggressive, so it may be a bit harder for a short while. But once I sort out all the SPAM things will go back to normal.
 
Thanks for your patience!
 
-Mark