DIALOGIC CORP

SCHEDULE 14D-1

SC 14D1

OFFER TO PURCHASE, DATED JUNE 7, 1999

EX-99.(A)(1)

LETTER OF TRANSMITTAL

EX-99.(A)(2)

NOTICE OF GUARANTEED DELIVERY

EX-99.(A)(3)

LETTER TO BROKERS

EX-99.(A)(4)

LETTER TO CLIENTS

EX-99.(A)(5)

GUIDELINES FOR CERTIFICATION OF TIN ON FORM W-9

EX-99.(A)(6)

FORM OF SUMMARY ADVERTISEMENT, DATED JUNE 7, 1999

EX-99.(A)(7)

PRESS RELEASES DATED JUNE 1 AND JUNE 7, 1999

EX-99.(A)(8)

AGREEMENT AND PLAN OF MERGER

EX-99.(C)(1)

STOCK OPTION AGREEMENT, DATED AS OF MAY 31, 1999

EX-99.(C)(2)

TENDER AND VOTING AGREEMENT AND IRREVOCABLE PROXY

EX-99.(C)(3)

TENDER AND VOTING AGREEMENT AND IRREVOCABLE PROXY

EX-99.(C)(4)

TENDER AND VOTING AGREEMENT AND IRREVOCABLE PROXY

EX-99.(C)(5)

TENDER AND VOTING AGREEMENT AND IRREVOCABLE PROXY

EX-99.(C)(6)

TENDER AND VOTING AGREEMENT AND IRREVOCABLE PROXY

EX-99.(C)(7)

EMPLOYMENT AGREEMENT FOR HOWARD G. BUBB

EX-99.(C)(8)