I am running vsftp on Redhat 9. I can get as far as connecting to the server. When I go to connect to the server it connects, but when I do a directory listing, the connection times out:
227 Entering Passive Mode (192,168,1,20,94,90)
ftp: connect: Connection timed out

Inside the pub dir there is 1 test file and a link to /mnt/mnt_share. Both have 777 read/write options (For testing purposes of course). Any idea where I might be going wrong?

the "entering Passive mode" seems to say that your ftp client is forced to switch to this version of the ftp protocol.
Ok, I can't tell you wich is the "active" or "passive" ftp protovol cuz there seems to be no straight line about it (and I'm not enought geek to read ftp RFC)

However, one is direct connection trought port 21 for every operation like :
Client(random > #30 000 port)------>Ftp(Port 21)
and it stay like this during all the session.

The "other one" is a first connection trought port 21 and then client and server negociate a port where they will continue connection, so something like :
Client(Radom > #30 000 port)------->Ftp(Random > #30 000 port)

Now the problem is that some firewall can't handle this second version, cuz they usually block they don't know. So make sure your firewall is ok (both client and server firewall) or use the "other" mode (active or passive, depending your client, no one has the same name but they usually all support both mode).

On Linux, you could use some special Nating module to make sure the connection will be keep alive even if it changes of port.

I guess this will require some more looking into. The only thing that I have found, not sure if this is what you were talking about, is something in the config file of the ftp server.
# Make sure PORT transfer connections originate from port 20 (ftp-data).
connect_from_port_20=YES

Then I went a head and opened up port 20 to allow data to come in and out, but still no such luck. What is this Nating module that you speak of?