[paramiko] Cannot find OS entropy source

[j_70 at comcast.net]

   I am getting the following error trying to run Paramiko in python 2.5 on WinXP. 

 from osrandom import OSRandomPool
  File "C:\Python25\lib\paramiko\osrandom.py", line 129, in <module>
    raise ImportError("Cannot find OS entropy source")
ImportError: Cannot find OS entropy source

Am I missing a dependent library?