SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


                                  SCHEDULE 13G


                    Under the Securities Exchange Act of 1934

                               (Amendment No. 3)*




                              DIALOGIC CORPORATION
- --------------------------------------------------------------------------------
                                (Name of Issuer)

                                  COMMON STOCK
- --------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                   252499 10 8
- --------------------------------------------------------------------------------
                                 (CUSIP Number)



*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).








                              CUSIP NO. 252499 10 8
- --------------------------------------------------------------------------------

(1)     Names of Reporting Persons.  S.S. or I.R.S. Identification Nos. of Above
        Persons:   Nicholas Zwick, ###-##-####
- --------------------------------------------------------------------------------
(2)     Check the Appropriate Box if a Member of a Group (See Instructions)  
           (a)                          (b)

- --------------------------------------------------------------------------------

(3)     SEC Use Only
- --------------------------------------------------------------------------------

(4)     Citizenship or Place of Organization:  United States
- --------------------------------------------------------------------------------

Number of Shares Beneficially Owned by  (5) Sole Voting Power:  2,986,899
   Each Reporting Person With
                                        (6) Shared Voting Power:  138,000 - held
                                            by a charitable trust.        
                                        (7) Sole Dispositive Power:    see box 5
                                        (8) Shared Dispositive Power:  see box 6

- --------------------------------------------------------------------------------

(9)     Aggregate Amount Beneficially Owned by Each Reporting Person:  3,124,899
- --------------------------------------------------------------------------------

(10)    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See 
Instructions)
- --------------------------------------------------------------------------------

(11)    Percent of Class Represented by Amount in Row (9): 19.5%
- --------------------------------------------------------------------------------

(12)     Type of Reporting Person (See Instructions):  IN
- --------------------------------------------------------------------------------







Item 1(a).  Name Of Issuer:  Dialogic Corporation
- --------------------------------------------------------------------------------

Item 1(b).  Address of Issuer's Principal Executive Offices:  1515 Route 10, 
Parsippany, New Jersey 07054
- --------------------------------------------------------------------------------

Item 2(a).  Name of Person Filing:  Nicholas Zwick
- --------------------------------------------------------------------------------

Item 2(b).  Address of Principal  Business  Office or, if None,  Residence:  c/o
Dialogic   Corporation,   1515   Route  10,   Parsippany,   New   Jersey   07054
- --------------------------------------------------------------------------------

Item 2(c).  Citizenship:  United States
- --------------------------------------------------------------------------------

Item 2(d).  Title of Class of Securities:  Common Stock
- --------------------------------------------------------------------------------

Item 2(e).  CUSIP No.:  252499 10 8
- --------------------------------------------------------------------------------

Item 3. If This  Statement  Is Filed  Pursuant to Rules  13d-1(b),  or 13d-2(b),
check whether the Person Filing is a

          (a) [ ] Broker or Dealer registered under Section 15 of the Act.

          (b) [ ] Bank as defined in section 3(a)(6) of the Act.

          (c) [ ] Insurance company as defined in section 3(a)(19) of the Act.

          (d)  [  ]  Investment  Company  registered  under  section  8  of  the
Investment Company Act.

          (e) [ ]  Investment  Adviser  registered  under  section  203  of  the
Investment Advisers Act of 1940.

          (f) [ ] Employee  Benefit  Plan,  Pension Fund which is subject to the
provisions of the Employee  Retirement  Income Security Act of 1974 or Endowment
fund; see Rule 13d-1(b)(1)(ii)(H).

          (g)  [  ]  Parent   Holding   Company,   in   accordance   with   Rule
13d-1(b)(ii)(G) (Note: See Item 7).

          (h) [ ] Group, in accordance with Rule 13d-1(b)(1)(ii)(H).

Item 4.  Ownership

          (a) Amount Beneficially Owned (as of December 31, 1997):

                  3,124,899

          (b) Percent of Class (as of December 31, 1997):

                  19.5%

          (c) Number of Shares as to which such person has:

              (i) sole power to vote or to direct the vote 2,986,899

              (ii)  shared  power  to  vote  or  to  direct  the  vote  138,000
                    held by a charitable trust                       ----------

              (iii) sole power to  dispose  or to direct  the  disposition  of
                    2,986,899

               (iv)  shared  power to dispose or to direct  the  disposition  of
                     138,000 - held by a charitable trust


Item 5. Ownership of Five Percent or Less of a Class. N/A


Item 6. Ownership of More Than Five Percent on Behalf of Another Person. N/A


Item 7.  Identification  and  Classification of the Subsidiary Which Acquired 
         the Security Being Reported on by the Parent Holding Company.  N/A


Item 8.  Identification and Classification of Members of the Group.  N/A


Item 9.  Notice of Dissolution of Group.  N/A


Item 10.  Certification.     N/A

                                    SIGNATURE

         After reasonable  inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.



                                                February 6, 1998
                                                    (Date)

                                        
                                                 NICHOLAS ZWICK



                                                 By:   /s/ Laura R. Kuntz
                                                       ____________________
                                                         (Signature)



                                               Laura R. Kuntz, Attorney-in-Fact
                                               _________________________________
                                                           (Name/Title)