I'm working on a 32-bit Ubuntu 10.10:
Ubuntu 10.10 \n \l
To download stuff from the DENX ftp we install ncftp.
sudo apt-get install ncftp
We are going to follow the following instructions for the ELDK 5.0 beta:
Connect to the denx ftp site (ask Denx for username and password)
ncftp -u <user-name> -p <password> ftp://ftp.denx.de
Which tag to use? Normally we take the tag that indicate a PSP release number from the Arago site. So take -  - which is .37 PSP4.02.00.07.
Same guy that did OE (Koen) is working Yocto as well.