We had similar issue last month. Users couldn't log in to OneWorld as it unable tot locate security server. "Waiting for security server" message displayed twice briefly and then "SEC0000007 - Unable to locate security server" message displayed. However some users managed to log in when retry button is clicked after this error messages, on OneWorld sign on screen, provided that they are already logged in to AS/400 green screen. In our setup, their AS400 system name and OneWorld system name are same. I couldn't test batch jobs under this log in. However problem disappeared later in the day with no apparent reason or fix. There was a problem in our corporate network so that external internet was not available approximately for the same period. Problem may be related to network or DHCP ect.
-Sathu