Already posted as:
Tehran plans a nuclear weapons test before March 20, 2006 ...
http://www.freerepublic.com/focus/f-bloggers/1562793/posts
with links to earlier non-Debka sources.
It appears Ken Timmerman's group (The Foundation for Democracy) is also reporting this.
This seems to be DUMBKA yet again simply repackaging info already publicly reported as supposedly coming from their secret inside sources (which don't exist, as best I can tell.)