Ok. Perhaps some more details:
1. Is this from an SSH session?
2. Is this from VIC client connection to ESX?
3. Is this from VIC client connection to VC to ESX?
4. What build numbers for VIC, VC (if applicable) and ESX?
5. Does this happen all the time?
6. Did it start recently?
7. If it started recently, what was the last thing you changed in the ESX/VC environment?