You are rigth. But this is not a hard task...

You can do a function like

function GetConStr()
begin
//Your must put the user/pa in somewhere, and replace the value here

MyConStr:=Format('Server=%s;User=%s;Pa=%s",[Server,User,Password]);

result:=MyConStr
end;

And assign it in the before open connection event (i don't remember the exact name for IB)

You get the idea?