University voice mail services will be suspended this weekend so that the system can be upgraded, the Harvard Telephone Office announced yesterday.

The voice mail system will be offline for about 12 hours starting at 10 p.m. Saturday while the technicians add 150 hours of memory and 12 additional lines to the system.

During the upgrade, subscribers will be unable to access their mail-boxes and callers will not be able to leave messages.

Jack Wise, client manager for the Office for Information Technology (OIT), said the upgrade was necessary to accommodate growth in the system, most of which was due to use by administrators rather than by students.

Wise said the system, which currently contains 11,110 mailboxes, 1,500 of which belong to students, ran out of memory a few weeks ago during Columbus Day weekend, preventing callers from leaving messages.

Upgrading the system should prevent such problems in the future, he said.

Wise said the office is trying to be "more proactive" in letting people know about the upgrade ahead of time.

The telephone office is requesting that subscribers delete all archived messages in order to expedite the upgrade.