Another bug in iPhone OS 2.1, which we have tested and reproduced, is that it will no longer fetch emails in the background while in sleep mode on battery power. It's most probably one of the power-saving tweaks introduced in 2.1, since Apple says that the 15-minute fetch interval is the worst wear on the battery because it never lets the phone go into deep sleep mode. This Apple discussion thread chronicles the problem at length. It's possible it'll be fixed in the next update—a reader tells us that Apple confirmed it's a "known problem" and that they are looking into it, but in the meantime, don't lean too hard on fetch. [Apple - Thanks Josh!]

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