BlackBerry users in North America were complaining of service problems again on Wednesday. Users of the BlackBerry outage newsgroup began reporting problems at around 6 am on the East Coast of the US related to scheduled maintenance on Research In Motion's network.

The issue appeared to get progressively worse, initially affecting about half of users in the Americas but eventually affecting all users, according to users of the newsgroup.

One user posted a note that he said came from his AT&T representative. The note called it a national BlackBerry outage that could affect email delivery for up to half of new BlackBerry users.

At noon on the East Coast, one user reported that AT&T said the problem was fixed but that email messages might still be delayed until the backup of messages was sent out.

Some users of the newsgroup said that they were able to receive messages all morning, although they were often delayed. RIM did not immediately comment on the issue.

Messages sent to and from BlackBerry devices pass through network operations centres that are operated by RIM. When RIM's network goes down, so does service to end-users.

The company had an outage just last week that lasted for about three hours and left users unable to send or receive messages or access the internet. That outage followed one that occurred in January, but that one was due to a problem with AT&T's network, so it affected BlackBerry users as well as iPhone and other AT&T mobile data customers.

RIM's most notorious network problem happened last year, with an outage that lasted overnight for many users in North America.

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