It turns out that AltaVista hasn't updated its regional indexes since April of this year, and the situation is likely to continue for the next two or three weeks. The plan is for all AltaVista sites to use one master index, rather than having separate country-specific indexes, as operated in the past. When this happens, the regional search results should become fresher.
AltaVista May Leave Users Searching
IDG, Aug. 29, 2001
Excellent summary of what happened to AltaVista's regional sites.
Where Have Your AltaVista Listings Gone?
About Web Search Guide, Aug. 29, 2001
Explains how the problems with AltaVista's regional listings were uncovered.