Workgroup computers not seeing each other at startup

[Chris]

I setup a peer to peer network for a local business with
two Dell desktops using a Linksys 8 port switch. They
are both running XP Pro and have the network setup. When
they first load Windows they do not see each other, if I
leave them sit for about five minutes they will then
communicate and the mapped drives work. If one of the
computers is rebooted then they stop communicating again
for about five minutes. Is there a way I correct this?
Any help is appreciated.

Chris