I read in the AE FAQ:
This was news to me…did Adobe change this to watch folders in general, or is there no hook for Deadline anymore? can you elaborate on what changed? The help doc for AE seems to read the same as far as watch folders go…
Yes, Adobe changed this:
blogs.adobe.com/sforde/2011/10/1 … ligations/
blogs.adobe.com/sforde/2011/12/0 … ns-part-2/
Deadline has always used aerender.exe to control the rendering process, and up until CS5.5, this command line application didn’t require a license. The reasons why Adobe changed this are covered in the blog posts above.
Cheers,
- Ryan
FYI.
I’m told things will be sorted in CS6, which is one of the reasons why we never bothered to upgrade to CS5.5. 
If you also look far enough down the comments on the first link Ryan provided, you will see that I have also asked for flexlm / floating licensing system to be considered by Adobe in the future