It's not happening here. Is this consistent? Is it always the Finder, or whatever the “previous application” is?

Always the finder.

Do you use any programs like LiteSwitchX? I do, but I don't know if this would affect things.

Nope. Fresh Tiger install, though I did copy over ~/Library/ Application Support/TextMate and ~/Library/Preferences/ com.macromates.textmate.plist.

Do you notice this only with the date dialog, not with the choose context dialog or other dialogs?

Just tested the choose context dialog and got the same issue.

Do you have your own CocoaDialog installed, or just the one that comes with TextMate?

Just the one that comes with TxMt.

Thanks for your assistance, hope this helps. Best regards,

Ben