[ale] Weird problem

[cfowler at outpostsentinel.com (Christoper Fowler)]

This problem is solved but I'm very confused.

I have 2 servers as guests under vmware server.  This
problem happened on both. 

The first server eth0 is 65.254.217.212 adn eth0:1 is 65.254.217.223.
The problem started when I set eth0 and then added the alias without
setting a netmask for the alias.  At our other colo facilty this setup 
worked fine so I never saw the problem.

Earlier a coworker called and said he could not access 65.254.217.212.
I could.  A traceroute on my end showed my last hop before
the machine was going to 65.254.208.9.  On his machine 208.1.  There
was a difference and I immediatley expected bad routing table in 208.1

when I tried to ping his dsl from the server 223 was stating that
the address was not reachable.  Once I fixed the netmask on eth0:1 to
match eth0 it worked and problem solved.

Why would that have worked on one net but not another?