New TNS protocol full client available for testing listener security
"ping , version , service , status change_password, help, reload, save_config, set connect_timout set display_mode, set log_directory , set log_file , set log_status , show , spawn stop"
The tool also supports full packet crafting (if you know what you are doing) and is based on the previous work by James Abendschan. The protocol has changed in 10g so this tool will be accompanied by a 10g version soon.
I have of course updated my Oracle Security tools page to include this tool.