When connectnig to domains using windows xp client, it asks for a username and password of an account with enough privileges to add your system to the network, but it does NOT ask this when connecting with a win9x client, my question: Why? and is there a way to bypass this in windows xp?

for your second question: no

for your first question: windows 98 isnt really a client for NTDS where windows NT, 2K & XP are. 98 has no security what so ever, you can press escape key, log onto the local machine and do whatever you damn well please locally, and w/ win98 you really dont join a domain, it just adds a field where you can type in the domain to auth to

I see. Are there any options for me if I have to use (and change to) multiple network config (thus, multiple domains) without asking for the network admins everytime, wich I really can't?