Has anyone got Inbound Emails to work on their installer stack (and non-standard Apache port)?

I am currently setting up a beta installation of Sugarcrm on my company's local server.
After a couple of weeks of effort, I have not been able to get Inbound Email working.
Unfortunately, I have to use this installer setup and a non-standard Apache port.

My Setup Details

Windows Server 2003, IIS 6
Sugarcrm 4.5.0f Bitrock WAMP Installer stack (Apache port 4848)

Symptoms

- Scheduler logs jobs in pollMonitoredInboxes Job Logs only when Apache is restarted
- But inbox only displays a couple of emails per day--and only ones that appear to be generated by a Trojan Horse on the email server
- Clicking "check mail" button causes email inbox function to crash (blank page appears)

N.B. My company's hosted production sugarcrm installation (not the bitrock stack) can successfully poll for Inbound Emails from the same accounts on the same Email Server.

Diagnostics and Troubleshooting

I have followed the Inbound Email and Windows Scheduler setup instructions in the FAQ's and guides.

a) Log Files
- no errors etc. with all debug features enabled in log4php.properties
- Corresponding output: DEBUG SugarCRM - ----->Scheduler Job completed successfully
b) Test Settings in Inbound Email Setup
- always displays "Your POP3 test connection was successful."
c) Windows Scheduler on Server
- confirmed scheduled task runs correctly without error (job run as administrator)
- running config.php manually produces no output
d) Diagnostic Test Itself
- all tests appear fine
e) Repair InboundEmail Accounts
- returns "All InboundEmail accounts repaired successfully!" Inbound Email still doesn't work.

Have I missed anything? I'd really appreciate any ideas/suggestions.

Thanks very much.

Patrick