San Jose, California-based Centigram Communications Corp has signed a letter of intent to acquire Voice-Tel Enterprises and its Voice-Tel Network unit. Voice-Tel, with more than $30m in annual revenue, provides voice messaging and voice processing services to more than 500,000 subscribers in North America, Australia and New Zealand. The deal would involve the issuance of some 2.3m shares of Centigram common stock. The exact number of shares would be adjusted downward if the closing price of Centigram stock during the five trading days before the Centigram stockholder meeting, called to approve the definitive agreement, exceeds $20 per share. If Centigram stock price is less than $10 per share during the measurement period, either Centigram or Voice-Tel would be able to elect not to consummate the transaction. Centigram would also assume up to $11.5m of outstanding debt of Voice Tel. The deal is expected to close in three months.