Try calling your ISP to see if they are blocking P2P. Whenever my ISP cuts off my connection every 24hours, a message pops up saying similar.
Also, are your firewalls (both Norton and XP's built-in one) configured to allow Phex to do it's job?

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iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

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