V§ Trap not being received

V§ Trap not being received

HI,
I am having problems with SNMP V3 Traps.Although  I can see that the V3 authentication is  correct by testing with GET commands (user, Auth, Priv passwords, I do not receive a trap entry in the SNMP Browser window. Using a sniffer, I can see that the trap is being correctly sent, and I can also receive V2C Traps so the Firewall is not an issue.
I am currently using V5.0 of the SNMP MIB Browser.

Perhaps this is just a setup problem.
Thanks for providing this great tool, and please help with this.

regards
John Read