I faced the same problem that you'all are facing. First of all let me tell you that IOU is available only to the Cisco Employees. So if you're not the one you can't use it. But that's not the case.! You can get you own IOU license if you have a blank VM with Linux installed. Web IOU will also do.
Just follow the steps:
1. Change the hostname and hostid in the new VM.
2. Change hostname with gns3-iouvm
type command as
now type command hostid, you should be able to see 00000000 ( 8 0's )
3. There is python crack which is available on net ( I am attaching the file )
4. Copy the CiscoIOUKeygen.py to your new VM using WinSCP.
5. Execute the file as per the link http://vmgeeks.wordpress.com/2012/07/21
6. Once thy python file has been executed you will be able to see your own license.
Need any help feel free to ask.