The Senate yesterday passed by voice vote a bill to upgrade and restructure the Foreign Service. It is the first major revision of the Foreign Service system in 34 years and follows by two years a revision of the Civil Service System.

With three exceptions, the bill is similar to legislation passed by the House recently. The Senate bill would keep the mandatory retirement at age 60. The house bill would raise it to 65.

Both bills would provide retirement benefits for a former spouse of a Foreign Service officer -- which usually means a divorced wife who had no chance to provide for her economic independence as she followed her husband from post to post. The Senate bill sets forth a formula for determining how much the former spouse should receive, while the House bill leaves this to the divorce court.

The major issue in dispute that must be settled in a House-Senate conference is the pay structure for the Foreign Service. The House bill linked this to the Civil Service pay scales which would mean raising Foreign Service pay. But the Senate bill leaves this to the discretion of the president.

An amendment to the Foreign Services Act that could have paid special benefits to the American hostages in Iran was rejected by the Senate, 43 to 41. Opponents of the amendment, sponsored by Sen. Jesse Helms (R-N.C.), said the benefits should be considered instead in a separate bill on the hostages that is pending in the Senate Finance Committee.

Some opponents felt the proposed retirement benefits for the hostages were too generous, exceeding even those granted prisoners of war.

Both House and Senate bills would create a new Senior Foreign Service, an elite group at the top similar to the senior executive service created within the Civil Service.