Annoying "CAKEPHP" query string

I made a simple CakePHP site which is randomly appending a query
string to the end of my urls. (e.g.: ?CAKEPHP=a0b80ba7a35fc3f6239...)
What is this and why is it happening?

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "CakePHP" group.
To post to this group, send email to cake-php@googlegroups.com
To unsubscribe from this group, send email to cake-php+unsubscribe@googlegroups.com
For more options, visit this group at http://groups.google.com/group/cake-php?hl=en
-~----------~----~----~----~------~----~------~--~---