UNIX does not support RC2_CFB Encryption, refer to knowledge base article. Therefore the encryption level has been set to "RSA R4 stream cipher (fast)" on the StarTeam Server.
However, the end-user on UNIX is still unable to login successfully. Note, this will also occur if no encryption, RC2_ECB and RC2_CBC had of been selected instead.
The StarTeam Cross Platform Client must be restarted for encryption changes to occur. Once the CPC has been restarted it will recognise that supported UNIX encryption has been configured for that specified IP address range.