Have just installed iMacG4 into office network pls help

Question

*Small office: 4 Macs: hardware upgrade in process*
We have two iMacs (Intel) which network perfectly. Click on network, see the other computer's name, click on it and you're in. That's the way it should be. No need to type a password and _you can see the other Mac's desktop._
I have just introduced an iMacG4 (powerPC) (it looks like a desklamp - that model) and now I'm going round in circles, which did not happen when I installed the other iMacs well over a year ago.
They're all running OSX10.4 so it's not an operating system issue.
They all have the same password.
Eventually I got the iMacG4 PowerPC to see an intel iMac (to copy over user data previously saved there from the old Mac which has now been taken out) by setting up user accounts at both ends, and I gave them both admin rights. I also checked permissions at both ends.
+I didn't have to do this a year ago when I installed the Intel iMacs, they've always been able to see each other's desktops and full disk contents!+
I have another one to instal before the Christmas break is over, but am reluctant to continue before I get this one sorted out.
What we need is all four Macs, all running OSX, all connected via the ethernet hub, all communicating smoothly, exactly as two of them already do.
*PLEASE DON'T TELL ME IT'S A POWERPC v. INTEL ISSUE!*
I think I've gone down the wrong trail in User Accounts, somehow. All I can think of is to delete the accounts I created today and start again......
FWIW I didn't have a Christmas break - it was cancelled due to being snowed in and being unable to get away. Therefore I'm doing this now, before the office restarts next Wednesday.
I hope it's a simple fix and that I'm just confused, reading too many Apple Help files. I hope so, I've got another one to instal, having previously gotten the data off the Mac it replaces, then 3-4 software licenses to instal on that one too.
Does this make sense? Have I said enough?

Answer 1

It was a simple fix, an answer which I got off another Mac forum, viz:
"We have several computers around here and we can freely connect and share data among all of them even though we do NOT have the same account or password on each of the machines. _The "trick" is each of the computers has been logged onto an account on each of the other machines using the userid and password of an account on the target computer._"
This was in response to the identical question posed here: the forum is www.finetunedmac.com
Thanks anyway. This is a wonderful place and has solved many other Mac problems.