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                                                                   Exhibit 10.13

                                                                   Ref: 20000909

                             EMPLOYMENT AGREEMENT #2
                                     BETWEEN
                      INFORMEDIX, INC. AND ROBERT H. BENSON

     This EMPLOYMENT AGREEMENT #2 ("Employment Agreement #2") dated as of the
1st day of September, 2000 (the "Effective Date") is between INFORMEDIX, INC., a
Maryland corporation (the "Corporation") with offices at 5880 Hubbard Dr.,
Rockville, MD 20852-4821 and Robert H. Benson residing at 6308 Valley Road,
Bethesda, Maryland, 208 17 (" Employee").

                                   WITNESSETH:

     WHEREAS, the Corporation and Employee entered into an employment agreement
dated August 9, 1999 ("Employment Agreement #l"), and the Corporation and
Employee both wish to supersede and replace Employment Agreement #l in its
entirety with this Employment Agreement #2 as of the Effective Date of this
Employment Agreement #2; and

     WHEREAS, the Corporation desires to continue to employ the Employee as its
President and Chief Operating Officer (" COO"), and the Employee desires to
continue such employment upon the terms and conditions set forth in this
Employment Agreement #2.

     NOW, THEREFORE, in consideration of the mutual covenants and obligations
hereinafter set forth, and the consideration, the receipt and sufficiency of
which is hereby acknowledged, the Corporation and Employee hereto agree as
follows.

1.   Employment Agreement #2 and Employment.

     A.   As of the Effective Date of this Employment Agreement #2, this
          Employment Agreement #2 shall supersede and replace Employment
          Agreement #l in its entirety as of the Effective Date of this
          Employment Agreement #2, and after the Effective Date of this
          Employment Agreement #2, Employment Agreement #l shall have no further
          force and effect.

     B.   The Corporation hereby continues to employ the Employee, and the
          Employee hereby continues his employment by the Corporation as
          President and COO of the Corporation upon the terms and conditions set
          forth in this Employment Agreement #2.

     C.   Employee will report to the Chief Executive Officer of the Corporation
          (the "CEO"), and to the Board of Directors of the Corporation (the
          "Board"), as so directed by the Board.

     D.   The Employee will perform the Employee's duties under this Employment
          Agreement #2 at the Corporation's offices at 5880 Hubbard Dr.,
          Rockville, MD 20852-4821.

2.   Term.

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     A.   The term of this Employee's employment under this Employment Agreement
          #2 shall commence on September 1, 2000 and end on the effective date
          of termination of employment (the "Term of Employment"), and payment
          of salary and other payments shall begin upon that date.

     B.   The Corporation may terminate the employment relationship at any time
          for any reason, with or without cause, by giving sixty (60) days prior
          written notice of such termination.

     C.   The Employee may terminate the employment relationship at any time for
          any reason, with or without cause, by giving sixty (60) days prior
          written notice of such termination.

3.   Duties.

     A.   The Employee shah perform such duties and services and shall be
          allocated such resources, consistent with the Employee's position, as
          may be assigned to him from time to time by the Chairman of the Board
          ("Chairman") and CEO of the Corporation. In furtherance of the
          foregoing, the Employee hereby agrees to perform well and faithfully
          such duties and responsibilities.

     B.   The Employee shall continue to be recommended for election to the
          Executive Committee of the Board (the "EC") at the next meeting of the
          Board, or by a special resolution circulated to the Board.

     C.   Employee shall perform the following:

          (1)  develop and implement, in conjunction with CEO, EC, and Board, a
               business development program focused on negotiating and closing
               patent licenses and corporate strategic alliances;

          (2)  assist the CEO and Chairman as needed in implementing the current
               InforMedix business plan and any revised business plans created;

          (3)  implement a licensing and corporate alliance program through
               soliciting interested third party licensees and corporate
               partners, conducting due diligence, formulating initial
               negotiation strategy/deal structure, assist in negotiating and
               closing transactions, and coordinating work with the
               Corporation's General Counsel and with outside counsel to create
               license agreements; and

          (4)  coordinate the Corporation's patent program, patent and trademark
               strategy, both inside and outside the U. S., patent enforcement
               strategy, and monitoring patent infringement by others.

     D.   Employee shall be subject to the terms and conditions of employment
          set forth in the Corporation's Policies and Procedures Manual, which
          may be revised unilaterally by the Corporation at any time. To the
          extent that there are any


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          inconsistencies between that Manual and this Employment Agreement #2,
          the terms of this Employment Agreement #2 shall control.

4.   Time to be Devoted to Employment.

     A.   Except for vacations, holidays and personal days and absences due to
          temporary illness, during the Term of Employment, the Employee shall
          devote the Employee's full time and energy to the business of the
          Corporation.

     B.   Employee shall conform to such hours of work as may from time to time
          reasonably be required of him and shall not be entitled to receive any
          additional remuneration for work for the Corporation outside the
          Employee's normal hours.

     C.   Employee shall be entitled to a total of twenty-six (26) days of
          annual paid time off ("Annual PTO"), as defined below, during this
          Employment Agreement. Annual PTO days not used by the Employee during
          one twelve month period may be accrued and used during the next twelve
          (12) months. Annual PTO includes the following time taken off from
          work for the Corporation for any of the following reasons: vacations;
          national holidays; illness; personal use; or any other purpose not
          otherwise restricted or prohibited by this Employment Agreement.

     D.   During the Term of Employment, the Employee shall not be engaged in
          any other business activity without the express written consent of the
          Corporation, except as follows:

          (1)  Employee may serve on the Board of Directors of up to two (2)
               other corporations that do not compete with, or are not in the
               same general business as the Corporation, with the written
               approval of the Board; and,

          (2)  Employee may exercise passive ownership of up to five percent
               (5%) of the securities in any other company that does not compete
               with, or is not in the same business as, the Corporation.

     E.   Employee hereby represents that he is not a party to any binding
          relationship or contract, which would be an impediment to entering
          into this Employment Agreement #2, and that he is permitted to enter
          into this Employment Agreement #2 and perform the obligations
          hereunder.

5.   Compensation; Reimbursement.

     A.   During the Term of Employment, the Corporation (or at the
          Corporation's option, any subsidiary or affiliate thereof) shall pay
          to the Employee an annual base salary ("Base Salary") of One Hundred
          Forty Thousand Dollars ($140,000), plus a stock option bonus
          calculated as set forth below (the "Bonus").

     B.   The Base Salary will be paid in bi-weekly installments, as follows:


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          (1)  if, in the opinion of the Executive Committee of the Board (the
               "EC"), the Corporation is able to pay the Base Salary in cash or
               cash equivalents, then, at the option of the Employee, Employee
               shall be paid either in cash or cash equivalents, or paid in
               options to purchase shares of the Corporation's common stock, in
               accordance with the method set forth in Subsection 5.B.(2) below;
               or

          (2)  if, in the opinion of the EC, the Corporation is unable to pay
               the Base Salary in cash or cash equivalents, then Employee shall
               be paid in options to purchase shares of the Corporation's common
               stock ("Base Salary Options").

     C.   The exercise price for Base Salary Options shall be One Dollar ($1.00)
          per each share of common stock covered by the option grant. Base
          Salary Options shall be granted on the last day of each biweekly
          period, as earned, and shall be vested and non-forfeitable upon grant.
          Base Salary Options first shall become exercisable one (1)year from
          the date of grant. The number of shares of common stock to be covered
          by such options each year shall equal one hundred and fifty percent
          (150%) of the Base Salary divided by ten (10). Base Salary Options
          shall be treated as non-qualified stock options as defined in the
          Corporation's Omnibus Stock Plan ("Plan").

     D.   The Bonus shall be paid in stock options, as provided for in Section 6
          below. All of the Bonus options shall be granted immediately upon the
          execution and delivery of this Employment Agreement #2. The exercise
          price for the Bonus options shall be $10 (ten dollars) per each share
          of common stock covered by the option grant. Bonus options shall vest
          according to the schedule set forth in Section 6 below, reflecting
          increases in the total annual revenues from all sources earned by the
          Corporation ("Revenues").

     E.   Each installment of the Bonus shall vest on January 1 following the
          fiscal year in which the Corporation achieves specified levels of
          accrued Revenues as determined by the Board of Directors under
          Generally Accepted Accounting Principles.

6.   Performance-Based Stock Options and Vesting

     A.   The Corporation grants to the Employee bonus options with respect to
          sixty-four Thousand (64,000) shares of the Corporation's common stock.
          Bonus options shall be treated as incentive stock options as defined
          in the Corporation's Plan. The exercise price with respect to the
          options granted under this Employment Agreement #2 (the "Option
          Shares") shall be $10 per share of common stock.

     B.   The Performance-Based Option Vesting schedule for 64,000 qualified
          shares of the Corporations common stock vest when the cumulative
          combined total of the Corporation's licensing fees and royalties
          actually received by the Corporation


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          ("License Fees")reach or exceed the revenue targets below. At each
          target level, vesting of 8,000 shares is achieved:

               1.   $250,000
               2.   $500,000
               3.   $1,000,000
               4.   $2,000,000
               5.   $3,000,000
               6.   $5,000,000
               7.   $7,000,000
               8.   $10,000,000

     C.   If the Employee ceases to be an employee or director of the
          Corporation, no Option Shares shall vest thereafter, except as
          specifically provided in Subsection 8.C. below.

7.   Review of Base Salary; Additional Bonus; Benefits Program.

     A.   The Base Salary shall be reviewed annually and be subject to increase
          at the option and in the sole discretion of the Board. The base salary
          shall be decreased only if there are across-the-board salary
          reductions applicable to all senior management employees of the
          Corporation.

     B.   At the close of the Corporation's fiscal year, Employee may be
          entitled to an additional bonus, as determined by the Board in its
          sole discretion, based on Employee's performance.

     C.   During the Term of Employment, when, and if, the Corporation creates
          any benefits programs for employees, the Employee shall be entitled to
          participate in those programs as they are added. Those programs may
          include: family medical and dental coverage; short and long term
          disability coverage; 401(k) or similar plans; and such other benefits
          as are made available from time to time to the employees of the
          Corporation. When, and if, the Corporation creates a benefits program
          for employees, the Corporation may unilaterally modify the benefits
          offered to Employee of the Corporation, and will notify the Employee
          in writing as to any such change.

     D.   The Corporation shall reimburse Employee, in accordance with its
          general practices and procedures from time to time for other employees
          of the Corporation, for all reasonable and necessary travel expenses,
          disbursement and other reasonable and necessary incidental expenses
          incurred by Employee for or on behalf of the Corporation in the
          performance of the Employee's duties under this Employment Agreement
          #2, upon presentation by the Employee to the Corporation of
          appropriate vouchers and/or other expense reports, and otherwise in
          accordance with its general practices and procedures as established
          from time to time by the Corporation.


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     E.   The Option Shares shall accelerate and become one hundred percent
          vested upon the occurrence of any of the following conditions
          (collectively referred to as the "Accelerated Vesting Conditions"):

          (1)  upon the dissolution or liquidation of the Company; or

          (2)  upon a reorganization, merger, or consolidation of the Company as
               a result of which the outstanding securities of the class of
               securities then subject to the Options are changed into or
               exchanged for cash or property or securities not of the Company's
               issue; or

          (3)  any combination thereof;

          (4)  upon a sale of substantially all of the property of the Company
               to, or the acquisition of the shares of common stock then
               outstanding by, another Corporation or person; or

          (5)  a Termination without Cause, as defined below, of the Employee.

8.   Effect of Termination of Employment.

     A.   For purposes of this Section of the Employment Agreement #2, the
          following definitions apply.

          (1)  "Termination Without Cause" is defined as any termination,
               including a "Voluntary Termination", "Death or Disability
               Termination", and a "Constructive Termination", but excluding a
               "Termination With Cause", all as defined below.

          (2)  "Termination With Cause" is defined as a termination initiated by
               the Corporation due to:

               (a)  the Employee's misconduct with respect to the business
                    and/or affairs of the Corporation or any subsidiary or
                    affiliate thereof, which action materially and adversely
                    affects the business and/or affairs of the Corporation or
                    any subsidiary or affiliate thereof; and/or

               (b)  the Employee failing, in any material respect, to observe
                    and perform the Employee's obligations and duties under this
                    Employment Agreement #2, after being given written notice by
                    the Board of an alleged failure to perform and a reasonable
                    opportunity to correct that failure; and/or

               (c)  the commission by the Employee of an act involving
                    embezzlement or fraud, or commission or conviction of a
                    felony.


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<PAGE>

          (3)  "Voluntary termination" is defined as a termination due to a
               resignation of employment by Employee, including a voluntary
               retirement by the Employee, unless the resignation constitutes a
               "Constructive Termination", as defined below.

          (4)  "Constructive Termination" shall occur when Employee resigns
               within six (6)months of any one or more of the following events:

               (a)  any reduction in the level of Base Salary, except for
                    across-the-board salary reductions applicable to all
                    management employees of the Employer; and/or

               (b)  a relocation of the Employee's place of employment to a
                    location more than sixty (60)miles from 5880 Hubbard Drive,
                    Rockville, Maryland 20852-4821.

               (c)  For purposes of the definition of Constructive Termination,
                    the hiring of a new President, CEO, and/or COO by the
                    Corporation will not be considered a Constructive
                    Termination. If such event occurs, Employee agrees to become
                    an Executive Vice President when, and if, a new President,
                    CEO, and/or COO, is hired, and/or a substantial investor,
                    individual or corporate, so requests, and/or the Board deems
                    it to be in the bests interest of the Corporation.

          (5)  "Death or Disability Termination" is defined as the following
               occurrences:

               (a)  If the Employee dies during the Term of Employment, the
                    Employee's employment under this Employment Agreement #2
                    shall be deemed to cease as of the date of the Employee's
                    death; or,

               (b)  the Corporation may terminate Employee's employment upon the
                    Employee's failure, by reason of any physical or mental
                    impairment, to perform the Employee's normal duties under
                    this Employment Agreement #2 for a period of ninety
                    (90)consecutive days or for ninety (90)days during any
                    consecutive 365-day period, with such disability termination
                    to become effective at the end of the applicable ninety
                    (90)day period.

               (c)  In the event of Corporation terminating Employee's
                    Employment for Disability Termination, Employee shall resign
                    as CEO, and shall still be entitled to serve as Chairman of
                    the Board of Corporation, if serving in that position at the
                    time of Disability Termination, unless Employee fails to
                    perform the duties of Chairman for a 365 day period.

     B.   Termination Without Cause.


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          Upon the termination of the Employee's employment under this
          Employment Agreement #2 pursuant to Termination Without Cause, neither
          the Employee nor the Employee's beneficiary or estate shall have any
          further rights or claims against the Corporation under this Employment
          Agreement #2, except to receive the following:

          (1)  the unpaid portion of the Base Salary computed on a pro rata
               basis to the date of such termination; and

          (2)  reimbursement for any expenses for which the Employee shall not
               have already been reimbursed;

          (3)  payment of all unused vacation time accrued through the date of
               termination; and

          (4)  Base Salary for six (6)months.

     C.   Upon a Termination Without Cause, a Constructive Termination, and/or
          Death or Disability Termination, Employee shall be entitled to the
          vesting of the Option Shares for the year of such termination, under
          the terms and conditions set forth in Section 6. above, the
          Performance-Based Stock Options and Vesting Section of this Employment
          Agreement #2.

     D.   Termination With Cause.

          Upon the termination of the Employee's employment under this
          Employment Agreement #2 pursuant to a Termination With Cause, as
          defined above, neither the Employee nor the Employee's beneficiary or
          estate shall have any further rights or claims against the Corporation
          under this Employment Agreement #2, except (

          (1)  to receive the following:

               (a)  the unpaid portion of the Base Salary computed on a pro rata
                    basis to the date of termination; and

               (b)  reimbursement for any expenses for which the Employee shall
                    not have theretofore been reimbursed; and

               (c)  payment of all unused vacation time accrued through the date
                    of termination; and

          (2)  less the following:

               (a)  all amounts owing to the Corporation; and

               (b)  the total value of any possible misappropriations from the
                    Corporation.


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          (3)  In addition, on the date of a Termination With Cause:

               (a)  all unvested options shall immediately terminate; and

               (b)  all unvested warrants and other unvested rights granted to
                    the Employee to purchase or otherwise receive stock of the
                    Corporation, shall immediately terminate; and

               (c)  all vested but unexercised options shall become immediately
                    exercisable, and Employee shall have the right to exercise
                    all, or a portion of, such vested but unexercised options,
                    subject to the following terms and conditions:

                    [l]  the Employee shall have twenty (20) days from the date
                         of a Termination With Cause to give written notice to
                         the Corporation of the Employee's intention to exercise
                         all, or a portion of, such vested but unexercised
                         options; and

                    [2]  within forty (40) days from the date of a Termination
                         With Cause, Employee must:

                         [a]  exercise all, or a portion of, such vested but
                              unexercised options; and

                         [b]  make payment in full to the Corporation in cash,
                              cash equivalents, or other immediately available
                              funds; and

                         [c]  otherwise complete the entire settlement process
                              for the exercise of all, or a portion of, such
                              vested but unexercised options.

     E.   Notwithstanding anything to the contrary in this Effect of Termination
          of Employment Section of this Employment Agreement #2, if any other
          officer or employee of the Corporation receives more favorable
          termination provisions than contained in this Effect of Termination of
          Employment Section of this Employment Agreement #2, then those more
          favorable termination provisions shall apply.

9.   Corporation's Rights to Intellectual Property of Employee.

     A.   The Employee shall promptly disclose, grant and assign ownership to
          the Corporation for its sole use and benefit, any and all inventions,
          improvements, information, copyrights, trademarks, service marks,
          intellectual property, and suggestions (whether patentable or not),
          for devices and/or products that hold medication, and/or devices,
          products, and/or programs that provide medication, whose function is
          prompting for, and ascertaining medication


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          compliance, and/or are portable technologies that are used by patients
          to capture data on medication compliance and/or health status, which
          Employee may develop, acquire, conceive or reduce to practice while
          employed by the Corporation (whether or not during usual working
          hours), together with all patent applications, letters patent,
          copyrights, trademarks, service marks, and other intellectual property
          (collectively "Intellectual Property"), and reissues thereof that may
          at any time be granted for or upon any such invention, improvement or
          information.

     B.   In connection therewith, the Employee shall:

          (1)  without charge, but at the expense of the Corporation, promptly
               at all times hereafter execute and deliver such applications,
               assignments, descriptions and other instruments as may be
               reasonably necessary or proper in the opinion of the Corporation
               to vest title to any such inventions, improvements, technical
               information, patent applications, patents, copyrights or
               reissues, and/or other Intellectual Property thereof in the
               Corporation and enable it to obtain and maintain the entire right
               and title thereto throughout the world; and

          (2)  render to the Corporation at its expense (including reimbursement
               to the Employee of reasonable out-of-pocket expenses incurred by
               the Employee and a reasonable payment for the Employee's time
               involved in case he is not then in its employ) all such
               assistance as it may reasonably require in the prosecution of
               applications for said patents, copyrights or reissues thereof, in
               the prosecution or defense of interferences which may be declared
               involving any said applications, patents or copyrights and in any
               litigation in which the Corporation may be involved relating to
               any such patents, inventions, improvements or technical
               information.

          (3)  As a pre-condition to the effectiveness of this Employment
               Agreement #2, Employee will sign the Corporation's
               Confidentiality, Non-Competition and Invention Assignment
               Agreements. If there is a conflict between such agreements and
               this Employment Agreement #2, this Employment Agreement #2 shall
               prevail including the Protection of Information Section of this
               Employment Agreement #2.

10.  Protection of Information.

     A.   Employee hereby covenants with Corporation that, throughout the term
          of the Employee's employment by Corporation, Employee will serve
          Corporation's best interests loyally and diligently. Throughout the
          course of employment by the Corporation and thereafter, Employee will
          not disclose or provide to any person, firm, corporation or entity
          (except when authorized by Corporation) any confidential information,
          materials, sales information, marketing plans or commercial
          activities; which are owned by the Corporation or which come into the
          possession of the Corporation from a third party under an obligation
          of confidentiality, including without limitation, information relating
          to trade secrets, business methods, products processes, procedures,
          development or experimental


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          projects, suppliers, customers lists or the needs of customers or
          prospective customers, clients, etc. (collectively "Confidential
          Information"), which Confidential Information, comes into Employee's
          possession or knowledge during the Term of Employment, and he will not
          use such Confidential Information for the Employee's own purpose or
          for the purpose of any person, firm, corporation or entity, other than
          the Corporation.

     B.   The provisions of this Section of the Employment Agreement #2 shall
          not apply to the following Confidential Information:

          (1)  Confidential Information which at the time of disclosure is
               already in the public domain;

          (2)  Confidential Information which subsequently becomes part of the
               public domain through no fault of the Employee;

          (3)  Confidential Information which becomes known to the Employee
               through a third party who is under no obligation of
               confidentiality to the Corporation; and

          (4)  Confidential Information which is required to be disclosed by law
               or by judicial or administrative proceedings.

11.  Non-Compete.

     A.   Employee agrees that during the Term of Employment and for a period of
          twenty-four (24)months following any termination of the Employee set
          forth in the Effect of Termination of Employment Section of this
          Employment Agreement #2, Employee agrees not to enter the employ of,
          directly or indirectly, or serve as an officer, director, employee,
          consultant, owner, partner, stockholder, agent, or in any other
          capacity, of or for, any person, company, or entity that owns,
          controls, manufactures, sells, leases, markets, licenses, and/or
          distributes -devices and/or products that hold medication, and/or
          devices, products, and/or programs that provide medication: whose
          function is prompting for, and ascertaining medication compliance;
          and/or are portable technologies that are used by patients to capture
          data on medication compliance and/or health status.

     B.   In the unlikely event that Employee breaches Employee's obligations as
          described in this Section, both parties agree that irreparable harm
          will have been caused to InforMedix. Therefore, in the event of a
          determination of such a breach by a court of competent jurisdiction,
          Employee hereby agrees that InforMedix shall be entitled to temporary
          or permanent injunctive relief, and to a judgment for damages caused
          by the breach, and any other equitable or legal remedies provided by
          applicable law or at equity.

12.  Notices.


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     A.   Notices and other communications under this Employment Agreement #2
          shall be in writing and shall be delivered personally or sent by
          nationally recognized overnight air courier or first class certified
          or registered mail, return receipt requested and postage prepaid,
          addressed as follows unless the party specifies a new address in
          writing:

          If to the Employee:       Robert H. Benson, Ph. D.
                                    6308 Valley Road
                                    Bethesda, Maryland 208 17

          If to the Corporation:    President
                                    InforMedix, Inc.
                                    5880 Hubbard Drive
                                    Rockville, MD 20852-482 1

          With a copy to:           General Counsel
                                    InforMedix, Inc.
                                    5880 Hubbard Drive
                                    Rockville, MD 20852-482 1

     B.   All notices and other communication given to any party to this
          Employment Agreement #2 in accordance with the provisions of this
          Employment Agreement #2 shall be deemed to have given to the date of
          delivery if personally delivered; on the business day after the date
          when sent if sent by air courier; and on the third business day after
          the date when sent if sent by mail, in each case addressed to such
          party as provided in this Section or in accordance with the latest
          unrevoked direction from such party.

13.  General Provisions

     A.   This Employment Agreement #2 contains the entire understanding between
          the parties and supersedes any prior written or oral agreements,
          understandings, term sheets, or other between them, with the exception
          of the specific agreements between the Corporation and the Employee
          specifically referenced in this Employment Agreement #2. This
          Employment Agreement #2 shall not be modified or waived except by
          written instrument signed by the parties.

     B.   This Employment Agreement #2 and any or all terms hereof may not be
          changed, waived, discharged, or terminated orally, but only by way of
          an instrument in writing signed by the parties.

     C.   There are no collective bargaining agreements affecting Employee's
          employment.

     D.   Employee acknowledges that this Employment Agreement #2 was made by
          the parties in Maryland and shall be governed and enforced in
          accordance with the laws of Maryland. without reference to the
          conflicts of laws of the State of Maryland or any other jurisdiction.
          Employee acknowledges that the state and federal courts of Maryland
          shall be the exclusive for a for the resolution of any


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          disputes concerning this Employment Agreement #2 or concerning
          Employee's employment with the Company and that he agrees to submit to
          the jurisdiction of those courts.

     E.   Employee acknowledges that, if he breaches any provision of this
          Employment Agreement #2, the Company will be irreparably harmed, that
          monetary damages alone may not be sufficient to adequately protect the
          Company from such breach, and that, in addition to any other remedy,
          the Company shall be entitled to recover all expenses incurred in
          enforcing these provisions, including attorneys' fees and court costs,
          and to a preliminary and permanent injunction enjoining such breach.

     F.   If any portion of this Employment Agreement #2 shall be found to be
          invalid or contrary to public policy, the same may be modified or
          stricken by a Court of competent jurisdiction, to the extent necessary
          to allow the Court to enforce such provisions in a manner which is as
          consistent with the original intent of the provisions as possible. The
          striking or modification by the Court of any provision shall not have
          the effect of invalidating the Employment Agreement #2 as a whole. In
          addition, if any valid federal or state law or final determination of
          any administrative agency or court of competent jurisdiction affects
          any provision of this Employment Agreement #2, then the provision or
          provisions so affected shall automatically be modified to conform to
          the law or determination and otherwise this Employment Agreement #2
          shall continue in full force and effect.

     G.   The section headings contained in this Employment Agreement #2 are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Employment Agreement #2.

     H.   This Employment Agreement #2 is personal in its nature and the parties
          hereto shall not, without the consent of the other, assign or transfer
          this Employment Agreement #2 or any rights or obligations under this
          Employment Agreement #2; provided, however, that the provisions hereof
          shall inure to the benefit of, and be binding upon the parties and
          their respective executors, administrators, personal representatives,
          heirs, assigns and successors in interest. And each successor of the
          Corporation, whether by merger, consolidation, transfer of all or
          substantially all assets, or otherwise and the heirs and legal
          representatives of the Employee.

     I.   The obligations of the General Provisions Section, the Corporation's
          Rights to Intellectual Property of the Employee Section, and the
          Protection of Information Section shall survive the termination or
          expiration of this Employment Agreement #2.

     J.   Both parties have read the foregoing Employment Agreement #2 in its
          entirety and voluntarily agree to each of its terms and conditions
          with full knowledge of such terms and conditions

     K.   The Corporation and Employee acknowledge and agree that any and all
          grants of stock options or restricted stock under this Employment
          Agreement #2 are made


                                       13
<PAGE>

          pursuant to the authorization and terms and conditions of the
          Corporation's Omnibus Stock Plan and Restricted Stock Agreement which
          shall be controlling except where expressly modified in this
          Employment Agreement #2.

     IN WITNESS WHEREOF, the parties have duly executed this Employment
Agreement #2 as of the date first above written.

INFORMEDIX, INC. ("Corporation")


By /s/ Bruce Kehr                           January 22, 2003
  --------------------------------          ---------------------------------
  Bruce Kehr, M.D.                          Date
  Chairman and CEO

EMPLOYEE ("Employee")


By /s/ Robert H. Benson                     January 22, 2003
  --------------------------------          ---------------------------------
  Robert H. Benson, M.D.                    Date


                                       14
<PAGE>

                                                                 Ref: 2001040301

                     AMENDMENT #l TO EMPLOYMENT AGREEMENT #2
                     BETWEEN INFORMEDIX AND ROBERT H. BENSON

     This Amendment #l to the Employment Agreement #2 Between InforMedix and
Robert H. Benson (the "Amendment# 1") dated as of the 5th day of February, 2001
and effective on January 1, 2001 (the "Effective Date") is between InforMedix,
Inc., a Delaware corporation ("Employer" or the "Corporation") with offices at
5880 Hubbard Dr., Rockville, MD 20852-4821 and Robert H. Benson residing at 6308
Valley Road, Bethesda, Maryland, 20817 ("Employee").

                                   WITNESSETH:

     WHEREAS, Employer has previously employed the Employee as its President and
Chief Operating Officer ("COO") under and pursuant to Employment Agreement #2
with Employee dated as of September 1, 2000 (the "Employment Agreement#2"); and,

     WHEREAS, both the Employer and the Employee wish to amend the Employment
Agreement #2 and have the Employee continue employment with the Employer upon
the terms and conditions set forth in this Amendment #l.

     NOW, THEREFORE, in consideration of the mutual covenants and obligations
hereinafter set forth, and the consideration, the receipt and sufficiency of
which is hereby acknowledged. Employer and Employee agree as follows.

1.   Effect of this Amendment #l.

     A.   All of the terms and conditions set forth in this Amendment #1 shall:

     (1) be effective as of the Effective Date, unless a different date is
specifically referred to in this Amendment #1; and

     (2) supersede and replace those sections of the Employment Agreement #2,
which they specifically change.

     B.   All other terms and conditions not specifically changed by this
          Amendment #1 shall remain in full force and effect in accordance with
          the terms and conditions of the Employment Agreement #2.

2.   Compensation; Reimbursement

          Section 5 of the Employment Agreement #2, entitled Compensation;
          Reimbursement, is replaced in its entirety by this Section 2 of this
          Amendment #1, entitled Compensation; Reimbursement.

     A.   Commencing on the Effective Date, Employer (or at Employer's option,
          any subsidiary or affiliate thereof)shall pay to the Employee an
          annual salary of

<PAGE>

          $140,000.00 (One Hundred Forty Thousand Dollars), with a minimum of
          $40,000 (forty thousand dollars)to be paid in cash (the "Salary"). The
          Salary will be paid in bi-weekly installments.

     B.   If it is determined by the Executive Committee of the Board of
          Directors of Employer (the "Executive Committee")that there are
          insufficient funds to pay any portion of the Salary in cash, then the
          portion of the Salary not paid in cash, up to the full amount of the
          Salary, w-ill be paid in the form of non-qualified stock options of
          Employer, as defined in Employer's Omnibus Stock Plan (" Plan"), with
          an exercise price per share of $1.00 (one dollar), which vest
          immediately when granted, and become exercisable one year after the
          date of each grant (the "Salary Options").

          (1)  The number of shares subject to the Salary Options (the "Salary
               Option Share(s)")will be determined by dividing the amount of the
               Salary not to be paid in cash, by the per share price of
               InforMedix Common Stock on the date of grant of the Salary
               Options (on the Effective Date of this Amendment #1 it is $10.00
               [ten dollars]per share), less the $1.00 (one dollar)exercise
               price. or $9.00 (nine dollars).

          (2)  For example, were $160,000.00 (one hundred sixty thousand
               dollars) of Salary not to be paid in cash, then, Salary Options
               to purchase 11, 111.111 (eleven thousand, one hundred eleven
               point one one one) Salary Option Shares would be granted.

          (3)  If Employer sells, or otherwise cause to be issued, any shares of
               InforMedix Common Stock, or other instruments convertible into
               InforMedix Common Stock, for less than $10.00 (Ten Dollars)per
               share (the "Revised Price Per Share"), then Employer shall issue
               to Purchaser, additional Salary Option Shares so that the Salary
               Option Shares equal the amount of the Salary not to be paid in
               cash, divided by the Revised Price Per Share.

     C.   Employer, at the election of the Board of Directors, may exercise a
          call on some or all of the issued, but unexercised Salary Options held
          by Employee as of the date of such call (a "Call"), and purchase those
          Salary Options from Employee within 60 (sixty) days of a Call, at a
          purchase price per Salary Option Share equal to the then-effective
          market price per share of InforMedix Common Stock, but in no event
          less than $10.00 (Ten Dollars)per share, less the $1.00 exercise
          price, and subject to the terms and conditions set forth below.

          (1)  At any time during a calendar year, Employer may exercise a Call
               to purchase some or all of the unexercised Salary Options earned
               by Employee at any time in that calendar year, up to and
               including the date of the exercise of a Call.

          (2)  Up to and including March 31st of any year, Employer may exercise
               a Call to purchase some or all of the unexercised Salary Options
               earned by Employee at any time in the preceding calendar year.


                                       2
<PAGE>

          (3)  Nothing in this Subsection of Amendment #1 shall authorize or
               permit Employer to purchase InforMedix Common Stock owned by
               Employee which had previously been subject to Salary Options of
               Employee, and which had previously been exercised by Employee and
               converted to InforMedix Common Stock.

3.   Performance-Based Stock Options and Vesting.

          Section 6 of the Employment Agreement #2, entitled Performance-Based
          Stock Options and Vesting, is replaced in its entirety by this Section
          3 of this Amendment #1, entitled Performance-Based Stock Options and
          Vesting.

     A.   Employer hereby issues to the Employee upon the Effective Date of this
          Amendment #1, 24,500 (twenty-four thousand, five hundred)
          performance-based stock options to purchase InforMedix Common Stock,
          in the form of non-qualified, incentive stock options of Employer, as
          defined in the Plan, with an exercise price of $10.00 (ten dollars)per
          share, which shall vest and be exercisable according to the schedule
          below, exercisable upon the vesting date of each grant, and otherwise
          subject to the terms and conditions of this Section 3. of Amendment #1
          (the "PB Options").

     B.   The PB Options to purchase InforMedix Common Stock will vest based
          upon the attainment of pre-determined and pre-assigned performance
          targets, as determined by the Board of Directors.

     C.   The PB Options will be for a three-year period, with one-third of the
          shares subject to the PB Options (the "PB Option Share(s)"), vesting
          in each of the three years of each grant (a "Grant").

     D.   The number of PB Option Shares subject to the PB Options for each
          Grant, will be 8,166.66 (eight thousand, one hundred sixty-six point
          six six), which will be eligible for vesting in each of the three
          (3)years of each Grant.

     E.   After the date that the Employee ceases to be an employee or director
          of Employer, no PB Options or PB Option Shares shall vest. except as
          specifically provided in Section 5. of this Amendment #1.

4.   Acceleration of Vesting of Salary Options and PB Options.

          Subsection 7.E. of the Employment Agreement #2 is hereby superseded by
          the following, which shall replace that Subsection in its entirety

     A.   The Salary Options and the PB Options shall accelerate and become one
          hundred percent vested and immediately exercisable, upon the
          occurrence of any of the following conditions (collectively referred
          to as the "Accelerated Vesting Conditions"):

          (1)  upon the dissolution or liquidation of the Company; or


                                       3
<PAGE>

          (2) upon a reorganization, merger, or consolidation of the Company as
          a result of which the outstanding securities of the class of
          securities then subject to the Options are changed into or exchanged
          for cash or property or securities not of the Company's issue; or

          (3) any combination thereof;

          (4) upon a sale of substantially all of the property of the Company
          to, or the acquisition of a majority of the shares of InforMedix
          Common Stock then outstanding by, another Corporation or person; or

          (5) a Termination without Cause of the Employee.

5.   Adjustment of Agreement and Amendment #l Options.

          A new-Section 7A is added to the Employment Agreement #2 as follow-s.

     7A.  Adjustment of Agreement and Amendment #l Options.

     A.   In the event that InforMedix issues shares of its InforMedix Common
          Stock or rights, options or warrants for, or securities convertible or
          exchangeable into InforMedix Common Stock, to any person or entity
          other than Employee (collectively referred to as a "Third Party"),
          entitling such Third Party to subscribe for or purchase shares of
          InforMedix Common Stock at a price per share that is lower at the
          record date than the exercise price of the Base Salary Options and
          Option Shares issued under the Employment Agreement #2, and Salary
          Options and/or the PB Options issued under this Amendment #l
          (collectively referred to as the "Agreement and Amendment #1 Options"
          and such event referred to as a "Dilutive Event"), the exercise price
          of the Agreement and Amendment #l Options shall be reduced to the
          exercise price or share price of the Dilutive Event.

          (1)  The new number of shares of InforMedix Common Stock purchasable
               upon the exercise of the Agreement and Amendment #l Options shall
               be determined by multiplying the old number of shares purchasable
               by the Agreement and Amendment, #1 Options, by the old exercise
               price of the Agreement and Amendment #1 Options, divided by the
               new-exercise price of the Agreement and Amendment# 1 Options.

          (2)  A Dilutive Event will not be deemed to have occurred for the sale
               or issuance of shares of InforMedix Common Stock (including
               options)to employees of InforMedix, that are approved by the
               Board, or the exercise of currently authorized options and
               warrants.

     B.   The number of Agreement and Amendment #l Options w-ill be adjusted in
          the same manner as other shares of InforMedix Common Stock issued and
          outstanding -as of the date of the Employment Agreement #2 for the
          Base Salary Options and Option Shares issued under the Employment
          Agreement #2, and as of the Effective Date of this Amendment #1 for
          the Salary Options and the PB


                                       4
<PAGE>

          Options issued under this Amendment #1 --in the event of, but not
          limited to, any of the following, which occur and which affect the
          InforMedix Common Stock: stock split; reverse stock split;
          recapitalization; and/or other adjustment.

     C.   For as long as the stock of InforMedix has not been registered under
          the United States Federal securities laws and/or state securities
          laws, the Agreement and Amendment #1 Options cannot be transferred or
          sold to another individual, corporation or entity unless permitted
          under the InforMedix Investors Rights Agreement, or agreed upon by a
          majority of the Board, and then only in compliance with applicable
          laws and regulations.

     D.   After the stock of InforMedix has been registered under the United
          States Federal securities laws and/or state securities laws, the
          shares issued as a result of exercise of the Agreement and Amendment
          #1 Options may be transferred or sold, but only in compliance with:
          the security laws of the United States of America; the security law-s
          of applicable states; all other applicable laws and regulations; any
          other restrictions placed on the transferability of the Agreement and
          Amendment #1 Options and agreed to by the Board of Directors of
          InforMedix, including but not limited to those by the underwriter or
          other investment banker with respect to the public offer, sale, and/or
          transfer of the stock of InforMedix, especially those shares of stock
          held by officers, directors, and insiders of InforMedix; and any other
          restrictions placed on the transferability of stock agreed to by the
          directors of InforMedix. Employee further agrees to have a legend
          placed on the certificates for the Agreement and Amendment #1 Options
          reflecting any of the provisions of this Amendment #1 and the
          Employment Agreement#2.

6.   Termination of Employment.

          Subsections 8. C. and 8.D. of the Employment Agreement #2 are hereby
          superseded by the following, which shall replace those Subsections in
          their entirety.

     C.   Upon a Constructive Termination and/or Death or Disability
          Termination, as defined in the Employment agreement #2, Employee shall
          be entitled to the vesting of the PB Options only for the year of such
          termination, under the terms and conditions as set forth in this
          Section 3 of this Amendment #l. Nothing in this Subsection shall limit
          or restrict the vesting of the Salary Options and/or Salary Shares for
          Employee.

     D.   Termination With Cause.

          Upon the termination of the Employee's employment under the Employment
          Agreement #2 pursuant to a Termination With Cause, neither the
          Employee nor the Employee's beneficiary or estate shall have any
          further rights or claims against Employer under this Amendment #1,
          except

         (1)  to receive the following:


                                       5
<PAGE>

               (a)  the unpaid portion of the Base Salary and any Salary Options
                    computed on a pro rata basis to the date of termination; and

               (b)  reimbursement for any expenses for which the Employee shall
                    not have theretofore been reimbursed; and

               (c)  payment of all unused vacation time accrued through the date
                    of termination; and

          (2)  less the following:

               (a)  all amounts owing to Employer; and

               (b)  the total value of any possible misappropriations from
                    Employer.

          (3)  In addition, on the date of a Termination With Cause:

               (a)  all unvested PB Options shall immediately terminate; and

               (b)  all unvested warrants and other unvested rights granted to
                    the Employee to purchase or otherwise receive stock of
                    Employer, shall immediately terminate; and

               (c)  all vested but unexercised Salary Options and PB Options
                    shall become immediately exercisable, and Employee shall
                    have the right to exercise all, or a portion of, such vested
                    but unexercised Salary Options and PB Options, subject to
                    the following terms and conditions:

                    [1]  the Employee shall have twenty (20)days from the date
                         of a Termination With Cause to give written notice to
                         Employer of the Employee's intention to exercise all,
                         or a portion of, such vested but unexercised Salary
                         Options and PB Options; and

                    [2]  within forty (40) days from the date of a Termination
                         With Cause. Employee must:

                         [a]  exercise all, or a portion of, such vested but
                              unexercised Salary Options and PB Options; and

                         [b]  make payment in full to Employer in cash, cash
                              equivalents, or other immediately available funds
                              for the exercise of the Salary Options and PB
                              Options; and


                                       6
<PAGE>

                         [c]  otherwise complete the entire settlement process
                              for the exercise of all, or a portion of, such
                              vested but unexercised Salary Options and PB
                              Options.

                    [3]  Any portion of vested but unexercised Salary Options
                         and PB Options, which are not exercised under and
                         pursuant to the terms and conditions of this Subsection
                         B.(3)(c)shall immediately terminate.

7.   General Provisions.

     A.   This Amendment #1 contains the entire understanding between the
          parties and supersedes any prior written or oral agreements,
          understandings, term sheets, or other between them, with respect to
          the matters covered by this Amendment #1.

     B.   This Amendment #1 and any or all terms hereof may not be changed,
          waived, discharged, or terminated orally, but only by way of an
          instrument in writing signed by both Employer and Employee.

     C.   Employee acknowledges that this Amendment #1 was made by the parties
          in Maryland and shall be governed and enforced in accordance with the
          law-s of Maryland, without reference to the conflicts of laws of the
          State of Maryland or any other jurisdiction. Employee acknowledges
          that the state and federal courts of Maryland shall be the exclusive
          for a for the resolution of any disputes concerning this Amendment #1
          or concerning Employee's employment with the Company and that he
          agrees to submit to the jurisdiction of those courts.

     D.   Employee acknowledges that, if Employee breaches any provision of this
          Amendment #1, the Company .will be irreparably harmed, that monetary
          damages alone may not be sufficient to adequately protect the Company
          from such breach, and that, in addition to any other remedy, the
          Company shall be entitled to recover all expenses incurred in
          enforcing these provisions, including attorneys' fees and court costs,
          and to a preliminary and permanent injunction enjoining such breach.

     E.   If any portion of this Amendment #1 shall be found to be invalid or
          contrary to public policy, the same may be modified or stricken by a
          Court of competent jurisdiction. to the extent necessary to allow-the
          Court to enforce such provisions in a manner which is as consistent
          with the original intent of the provisions as possible. The striking
          or modification by the Court of any provision shall not have the
          effect of invalidating the Amendment #1 as a whole. In addition, if
          any valid federal or state law-or final determination of any
          administrative agency or court of competent jurisdiction affects any
          provision of this Amendment #1, then the provision or provisions so
          affected shall automatically be modified to conform to the law or.
          determination and otherwise this Amendment #1 shall continue in full
          force and effect.


                                       7
<PAGE>

     F.   The section headings contained in this Amendment #1 are for reference
          purposes only and shall not affect in any way the meaning or
          interpretation of this Amendment #l.

     G.   This Amendment #1 is personal in its nature and Employer and Employee
          shall not, without the consent of the other, assign or transfer this
          Amendment #1 or any rights or obligations under this Employment
          Agreement #2; provided, however, that the provisions hereof shall
          inure to the benefit of, and be binding upon the parties and their
          respective executors, administrators, personal representatives, heirs,
          assigns and successors in interest, and each successor of Employer,
          whether by merger, consolidation, transfer of all or substantially all
          assets, or otherwise and the heirs and legal representatives of the
          Employee.

     H.   he obligations of the General Provisions Section shall survive the
          termination or expiration of this Amendment #1.

     I.   Both parties have read the foregoing Amendment #1 in its entirety and
          voluntarily agree to each of its terms and conditions with full
          knowledge of such terms and conditions

     J.   Employer and Employee acknowledge and agree that any and all grants of
          Salary Options and PB Options under this Amendment #1 are made
          pursuant to the authorization and terms and conditions of the
          Employer's Omnibus Stock Plan and Restricted Stock Agreement which
          shall be controlling except w-here expressly modified in this
          Amendment #1.

     IN WITNESS WHEREOF, the parties have duly executed this Amendment #1 as of
the date first above written.

INFORMEDIX, INC. ("Corporation")


By: /s/ Bruce Kehr, M.D.                          May 21, 2001
   -----------------------------------            --------------------------
   Bruce A. Kehr, M.D.                            Date
   Chairman and CEO

EMPLOYEE ("Employee")


By: /s/ Robert H. Benson                          May 21, 2001
   -----------------------------------            --------------------------
   Robert H. Benson, Ph.D.                        Date


                                       8
<PAGE>

                                                                   Ref: 20011009

                      AMENDMENT TO EMPLOYMENT AGREEMENT #2
                                     BETWEEN
                    INFORMEDIX, INC. AND DR. ROBERT H. BENSON

     This Amendment to EMPLOYMENT AGREEMENT #2 ("Employment Agreement #2") dated
as of the 1st day of September, 2001 (the "Effective Date") is between
INFORMEDIX, INC., a Maryland corporation (the "Corporation") with offices at
5880 Hubbard Dr., Rockville, MD 20852-4821 and Dr. Robert H. Benson residing at
6308 Valley Road, Bethesda, Maryland, 208 17 ("Employee").

                                   WITNESSETH:

     WHEREAS, the Corporation and Employee entered into an employment agreement
dated September 1, 2000 ("Employment Agreement #2"), and the Corporation and
Employee both wish to amend Employment Agreement #2 as of the Effective Date
above; and

     WHEREAS Employee has voluntarily resigned as President and Chief Operating
Officer of the Corporation to assume the position of General Counsel and Chief
Patent Counsel of the Corporation; and

     WHEREAS, the Corporation desires to continue to employ the Employee as its
General Counsel and Chief Patent Counsel, and the Employee desires to continue
such employment upon the terms and conditions set forth in this Amendment to
Employment Agreement #2.

     NOW, THEREFORE, in consideration of the mutual covenants and obligations
hereinafter set forth, and the consideration, the receipt and sufficiency of
which is hereby acknowledged, the Corporation and Employee hereto agree to the
following modified provisions which shall supersede and replace comparable
provisions under Employment Agreement #2. All other unmodified provisions of
Employment Agreement #2 shall remain in full force and effect.

3.   Duties.

     C.   Employee shall perform the following:

          (1)  Assist the CEO and Chairman, President, and Board of Directors as
               needed in advising the Corporation on matters of corporate law,
               and in negotiating various transactions; and

          (2)  Draft Agreements and other legal documents on behalf of the
               Corporation; and

          (3)  Prepare and file patent applications, and coordinate the
               Corporation's patent program, patent and trademark strategy, both
               inside and outside the U. S., patent enforcement strategy, and
               monitoring patent infringement by others.
<PAGE>

Amendment to Employment Agreement #2 Between                     Ref:  20011009
InforMedix and Robert H. Benson                               Page 2 of 2 Pages


4.   Time to be Devoted to Employment.

     A.   Except for vacations, holidays and personal days and absences due to
          temporary illness, during the Term of Employment, the Employee shall
          devote the Employee's one half time and energy to the business of the
          Corporation.

     D.   During the Term of Employment, the Employee may be engaged in any
          other business activity without the express written consent of the
          Corporation, except as follows:

          (1)  Employee may serve on the Board of Directors of up to two
               (2)other corporations that do not compete with, or are not in the
               same general business as the Corporation, with the written
               approval of the Board; and,

          (2)  Employee may exercise passive ownership of up to five percent
               (5%)of the securities in any other company that does not compete
               with, or is not in the same business as, the Corporation.

5.   Compensation; Reimbursement.

     A.   During the Term of Employment, the Corporation (or at the
          Corporation's option, any subsidiary or affiliate thereof)shall pay to
          the Employee an annual base salary ("Base Salary")of Seventy Thousand
          Dollars ($70,000), plus a stock option bonus calculated as set forth
          in Employment Agreement #2.

     IN WITNESS WHEREOF, the parties have duly executed this Amendment to
Employment Agreement #2 as of the date first above written.

INFORMEDIX, INC. ("Corporation")


By: /s/ Bruce Kehr, M.D.                          January 22, 2003
   -----------------------------------            --------------------------
   Bruce Kehr, M.D.                               Date
   Chairman and CEO

EMPLOYEE ("Employee")


By: /s/ Robert H. Benson                          January 22, 2003
   -----------------------------------            --------------------------
   Robert H. Benson, Ph.D.                        Date