Melody,
I have exactly the same issue. I have 4 accounts, two on dot mac and two from my business, all four are using IMAP service. The two business accounts have suddenly stop working correctly (deleting "Trashed" mail after one week even though the setting is set to never delete)
1.8 G5 Power Mac Mac OS X (10.3.8) and a iBook G4 800Mhz
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