When will IA have it's own custom telnet client ?
It is in the works, but it hasn't got a high priority, since not many people are using telnet anymore.
What will the telnet client contain ?
Everything :) No, it will have Kermit, X,Y, and Z-Modem, possibly DBCS support, and definately scrollback, and integration into the other parts of IA, like the quicklist and address book.
How can you say that IA supports telnet when it hasn't got a client ?
Because Internet Adventurer does support telnet, by utilising OS/2's standard telnet client, until IA's own telnet client is ready.