Is that folder included in any items that appear in Spotlight's Privacy pane? Also, is the folder checked in Spotlight's Search Results pane?
No, not in the Privacy pane. And, yes, Folders is checked off in Search Results
I am now "post-OnyX" and I've done a bit more testing. It seems that the folder in question isn't the only one that Spotlight doesn't want to find. It's not finding any folder in Mail.
I've also tried Kevin's command-F at the Finder level and the result is the same - nothing from Mail.
EDIT: I changed the search parameter and asked command-F to find PDFs with the word and it found PDFs attached to Mail messages.
I am now going to try removing the spotlight.plist from my User preferences.
EDIT: Done, no change.
