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                                                                 EXHIBIT 10.17

                            PURCHASE AGREEMENT #10152


1.       AGREEMENT: This Agreement states the terms under which Cielo
         Communications, Inc. located 325 Interlocken Parkway, Broomfield,
         Colorado (hereinafter referred to as BUYER or Cielo) and XeTel Corp.,
         with place of business located at 2105 Gracy Farms Lane, Austin, Texas
         (hereinafter referred to as SELLER or XeTel) will conduct business with
         each other and to identify how such business will be conducted.

         When Cielo or BUYER is referred to in this agreement, it refers to
         Cielo Communications, Inc. and its current or future facilities
         worldwide.

2.       CONTRACT TERM: This Agreement takes effect on June 1, 1998, and will
         remain effective for an initial term of one (1) year. Thereafter, this
         Agreement shall automatically renew itself for successive one-year
         term, unless terminated pursuant to Section 23 below.

         2.1.     BUYER and SELLER will review the terms and conditions of this
                  Agreement to determine if changes need to be made. These
                  reviews will occur when the BUYER and/or SELLER make the
                  request for such a review. Any change will only be effective
                  when made in writing and signed by authorized representatives
                  of both BUYER and SELLER.

3.       SCOPE: SELLER agrees to sell to BUYER and BUYER may purchase from
         SELLER those part numbers for which SELLER is currently approved as a
         source of supply as referenced in the attached Schedule A.

         3.1.     BUYER shall have the right to make additions or subtractions
                  to the list of items in Schedule A. Pricing for additional
                  products shall be established at a value reflective of an
                  annual forecast and will use the same formula for calculating
                  the price that is used for existing assemblies in Schedule A,
                  subject to mutual agreement of the parties. The pricing will
                  be reviewed on a quarterly basis and adjusted according to the
                  forecasted volumes from the Buyer. SELLER agrees to adjust the
                  formula to meet goals identified in Section 13.

         3.2.     BUYER will supply documentation to the SELLER to assist SELLER
                  in procuring components to assemble items in Schedule A.
                  SELLER agrees to procure components approved per BUYER
                  documentation and only those part numbers listed in BUYER
                  specifications. If for some reason any component does not meet
                  BUYER specification, SELLER must notify BUYER for approval
                  prior to using the said component in any assembly. BUYER will
                  provide SELLER with new documentation or provide SELLER with a
                  Deviation Authorization if approval is granted. SELLER must
                  secure the new documentation or Deviation Authorization in
                  writing before using the component.

         3.3.     BUYER reserves the right to purchase some or all of the items
                  identified in Schedule A from other suppliers in the event
                  that BUYER deems it appropriate to do so, exercising its
                  independent business judgment. Under such circumstances, BUYER
                  will update its forecasts to reflect the necessary changes and
                  to allow SELLER to adjust forecasted demand accordingly.

4.       FORECASTS: BUYER will provide a rolling annual forecast to the SELLER
         for all items on Schedule A on monthly basis at minimum. BUYER shall
         not be obligated to purchase the exact forecasted quantity of any
         Schedule A items from SELLER, this Agreement being intended merely to
         establish the terms, conditions, and prices applicable when and if the
         BUYER does so purchase.

         4.1.     BUYER will provide SELLER with an annual Purchase Order (PO).
                  This PO will provide SELLER with the BUYER'S best estimate of
                  its long term forecast. The PO will specify the part number,
                  revision level, and quantity to be shipped or scheduled to be
                  released. BUYER will release against this PO based on
                  individual Module usage or by KANBAN trigger or other
                  notification methods.

5.       PRODUCTION AUTHORIZATION: SELLER has authorization to assemble and test
         the PO quantities as released by BUYER plus sufficient inventory to
         fill Module requests as defined by Cielo's Master Planning Schedule
         (MPS). Shipments to be made so Modules are on BUYER'S dock to meet
         delivery requirements as defined in Section 15.1.2.

         5.1.     BUYER will maintain cancellation rights for all assemblies
                  outside a 60-day rolling window unless SELLER was authorized
                  in writing by BUYER to produce assemblies outside that window.


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998


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                            PURCHASE AGREEMENT #10152


         5.2.     The PO will be revised by the BUYER as necessary and sent to
                  SELLER. At a minimum, SELLER agrees to adjust its internal
                  schedule for all PO deliveries the first week of every month
                  and more often if there are significant schedule changes.
                  SELLER shall notify BUYER of any delivery issues according to
                  Escalation Requirements as defined in Schedule D.

6.       RAW MATERIALS: BUYER material liability shall be limited to the
         Strategic Inventory Levels established in Schedule C for Non-Cancelable
         Non-Returnable (NCNR) components, excess due to minimum order quantity
         and for those long lead time materials required to sustain production
         forecasts and approved by the BUYER. Management of Min/Max levels for
         all components will be the responsibility of the SELLER. BUYER will
         assume responsibility for material required to support end of product
         life only if BUYER approves quantities purchased by SELLER.

         6.1.     BUYER may negotiate contracts with OEM's for components it has
                  specified. SELLER may piggyback these contracts, subject to
                  OEM approval. Contracts and pricing are to be used exclusively
                  for BUYER'S assemblies. Any cost savings from a BUYER'S
                  contract is to be passed directly to BUYER. Negotiation of
                  these contracts may require pricing to be adjusted during the
                  term of this agreement. BUYER and SELLER will work together to
                  determine price impact and cut in date. At that time, Schedule
                  A will be updated to reflect the new pricing. BUYER will use
                  reasonable effort to secure any authorizations needed by the
                  SELLER to procure any proprietary components. SELLER will
                  receive a copy of all such authorizations from BUYER if
                  needed.

7.       CAPACITY SURGE DEMAND: SELLER agrees to make every reasonable effort to
         ensure that, upon notice from BUYER, delivery quantities on order can
         be increased to match actual demand. This surge capacity may be
         contingent upon material availability, labor availability and equipment
         capacity. BUYER and SELLER must mutually agree on the surge plan.
         Strategic Inventory Levels established in Schedule C are to support
         such surges in BUYER demand. New designs or new releases of present
         designs may be an exception as the Strategic Inventory Levels are not
         yet secured.

8.       STANDARD LEAD TIMES GOAL/EXPECTATION: BUYER and SELLER agree to work
         together to drive toward the shortest possible lead-time to support
         BUYER customer requirements.

         8.1.     GOAL SETTING: As part of the Quarterly Meeting Review process,
                  SELLER and BUYER will assess lead time needs, develop goals
                  and plans for lead time reduction, and review progress toward
                  the established goals.

         8.2.     LONG-TERM OBJECTIVE: Assuming the materials pipeline is full
                  it is the long term objective to reduce manufacturing lead
                  time from receipt of order to shipment of finished product to
                  designated carrier from an initial 10 working days to a
                  maximum of 3 working days within 120 days of mutually agreed
                  start date for that particular assembly.

9.       RESCHEDULES AND CANCELLATIONS:

         9.1.     Provided no constraints per section 8.0, BUYER will provide a
                  rolling twelve month forecast for order management purposes.
                  The initial ninety (90) days is to be considered `firm',
                  supported by actual purchase orders for the demand
                  requirements. Within the first thirty (30) days, BUYER demand
                  may be adjusted up by 20% or down 0% of the production plan
                  loaded on SELLER'S order book during this period. Thirty-one
                  to sixty (31 to 60) days BUYER demand may be adjusted up by
                  50% or down by 20% of the production plan loaded on SELLER'S
                  order book during this period. Sixty-one to ninety (61-90)
                  days, BUYER demand may be adjusted up by 75% of the production
                  plan loaded on SELLER'S order book during this period. Greater
                  than sixty (60) days, BUYER may reschedule or cancel 100% of
                  planned demand. Buyer will be liable for material in
                  accordance with Section 6.

10.      PRICING: Will be in US Dollars and will be the same for all BUYER'S
         facilities, regardless of ordering or delivery location as subject to
         provisions of Section 14.1.1.

         10.1.    Pricing for items covered by this Agreement is listed in
                  Schedule A.

                  10.1.1.  Pricing includes packaging to good commercial
                           standards or when specified, to BUYER Procurement
                           Specifications as well as chemicals, supplies and
                           consumable materials needed to make BUYER products.

         10.2.    Pricing for all items listed in Schedule A is firm for the
                  duration of this agreement. Exceptions to this may be
                  permitted upon mutual agreement of the parties due to:


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998


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                            PURCHASE AGREEMENT #10152


                  10.2.1.  Cost of material changes beyond the control of SELLER
                           and agreed upon by BUYER and SELLER. Refer to
                           Schedule D for Escalation Schedules.

                  10.2.2.  BUYER specification revision changes, which cause
                           SELLER'S manufacturing costs to change.

                  10.2.3.  Market conditions which cause SELLER'S pricing to be
                           non-competitive will permit BUYER to reopen
                           negotiations to reduce pricing.

                  10.2.4.  Cost reduction projects by SELLER and/or BUYER will
                           permit either SELLER or BUYER to reopen negotiations
                           to reduce pricing.

                  10.2.5.  Significant forecast quantity increases or decreases
                           will permit BUYER and/or SELLER to reopen
                           negotiations to adjust pricing.

                  10.2.6.  Changes in Material Acquisition Service fee based on
                           total annual material purchases as detailed in
                           Schedule E.

         10.3.    Pricing changes of any kind will take effect only after BUYER
                  and SELLER have reached agreement regarding them via a written
                  revision of Schedule A.

11.      PURCHASE PRICE VARIANCES (PPVs): PPVs for all components needed to
         build product as listed in Schedule A will be authorized per occurrence
         by the Buyer. These PPVs will be calculated on the actual price paid
         compared with the PO pricing for the last quarter for both increases
         and decreases. PPV will be added to POs as separate itemized NRE line
         items.

         11.1.    Individual PPVs of significant impact (greater than $15,000)
                  may be addressed sooner than the quarterly update if deemed
                  necessary by the BUYER or SELLER.

12.      SAFETY STOCK:

         12.1.    Finished Goods Safety Stock. SELLER agrees to hold up to two
                  weeks of finished goods inventory. These quantities will be
                  mutually agreed upon by BUYER and SELLER, based on the
                  forecast provided pursuant to Section 9.1. At the end of each
                  month, SELLER will provide BUYER with a rolling inventory
                  aging report, and SELLER may invoice BUYER for any finished
                  goods that have been held by SELLER for more than 30 days at
                  Net 30 days. Buyer shall have the right to reduce its forecast
                  provided pursuant to Section 9.1 for the 30-day period
                  following the date of such invoice by the amount of any such
                  inventory invoiced to BUYER. In addition, BUYER agrees to be
                  liable for such finished goods in the event of cancellation by
                  BUYER of this Agreement or changes or modifications made by
                  BUYER via an Engineering Change Order (ECO) or Deviation
                  Authorization. Finished goods inventory levels are documented
                  in Schedule A. For purposes of this Section 12, all inventory
                  accounting shall be based on the FIFO method.

         12.2.    Raw Material Safety Stock: The raw material safety stocks will
                  be determined in the Strategic Inventory Level Schedule
                  (Schedule C) at no additional cost to the BUYER. Safety stock
                  levels will be reviewed and adjusted at least once per
                  quarter. BUYER agrees to be liable for these materials in the
                  event of changes or modifications made by the BUYER via an
                  Engineering Change Order (ECO), Deviation Authorization,
                  schedule reduction, quantity reduction or cancellation, or
                  contract termination by BUYER or SELLER. If circumstances
                  require SELLER to carry excessive raw material safety stock,
                  in the event of last time buys, the safety stock adder will be
                  1% per month.

13.      TOTAL COST, QUALITY, AND MANUFACTURABILITY IMPROVEMENTS:

         13.1.    GOAL AND EXPECTATIONS

                  13.1.1.  PRIMARY: To ensure that SELLER'S products and
                           services provide to BUYER a competitive advantage in
                           worldwide markets.

                  13.1.2.  SECONDARY: To improve SELLER'S costs of product and
                           services toward being the lowest cost on a global
                           basis.


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998


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                            PURCHASE AGREEMENT #10152

         13.2.    ON-GOING CONTINUOUS COST IMPROVEMENT GOALS

                  13.2.1   SELLER agrees to make continuous process
                           improvements, both with and without assistance from
                           BUYER, which will provide cumulative annual pricing
                           reductions Goals to BUYER totaling at least 2.5% of
                           the BUYER'S sell price less SELLER'S tightly
                           controlled materials, such as the Optical
                           Sub-Assemblies. This reduction does not include the
                           material reduction that is a result of BUYER level
                           contracts as defined in Section 7.

                  13.2.2   When cost reductions are identified by the SELLER,
                           the savings will generally be shared with the BUYER
                           on an equal (50/50) basis for 6 months after the
                           implementation. After 6 months the total cost
                           reduction will be reflected in Schedule A pricing.
                           SELLER may choose to pass on a larger percentage to
                           BUYER in order to meet the annual cost reduction goal
                           outlined in section 13.2.1. BUYER may agree to extend
                           the 6-month period to allow the SELLER to recapture
                           costs associated with implementation of a cost
                           reduction.

14.      FREIGHT:

         14.1.    All pricing is F.O.B. SELLER'S manufacturing facility.

         14.2.    Freight carrier to be specified to the SELLER by the BUYER. If
                  a product requires return for rework as under warranty, SELLER
                  should bear all costs associated with freight back to SELLER,
                  then freight for returning the goods to BUYER, including
                  duties, custom fees, excise taxes, etc.

         14.3.    LATE SHIPMENTS

                  14.3.1.  CAUSED BY SELLER: Freight charges and other
                           applicable expedite charges, that are over and above
                           the normal charges, which may be necessary to deliver
                           the product to BUYER will be paid for by SELLER.
                           SELLER is to contact the BUYER for freight transit
                           instructions. (NOTE: If the BUYER request expedited
                           air freight of these shipments, SELLER agrees to pay
                           for these additional expedited air freight costs.)

                  14.3.2.  CAUSED BY BUYER: When special handling is required to
                           meet an unusual demand specified by the BUYER,
                           SELLER'S special handling charges will be reimbursed
                           by the BUYER.

15.      PERFORMANCE MEASURES: SELLER and BUYER will periodically review
         performance according to Schedule B. During these periodic reviews,
         SELLER and BUYER will jointly establish goals for improvement in all
         areas. If SELLER continuously fails to improve upon performance issues
         or ignores requests by BUYER to maintain acceptable performance levels,
         BUYER may adjust the level of business given to SELLER, up to and
         including the termination of this Agreement per Section 24.

         15.1.    GOALS: Long Term: 100% Quality Acceptance Rate; 100% On-Time
                  Delivery Performance.

                  15.1.1.  QUALITY PERFORMANCE: Based upon the number of lots of
                           product received which meet BUYER'S specifications.
                           SELLER'S short-term goal is 99.7% acceptance by
                           October 1998 based on 6 month moving average.

                  15.1.2.  ON-TIME DELIVERY PERFORMANCE: Based upon the
                           quantities of acceptable quality product which arrive
                           on BUYER'S dock on the specified dock date or up to 5
                           working days earlier. SELLER'S short-term goal is 98%
                           on time by October 1998 based on 6 month moving
                           average.

16.      SHIPPING QUANTITY VARIANCES: No variance from the delivery quantities
         scheduled are allowed unless other arrangements are agreed to by the
         appropriate BUYER. SELLER will notify BUYER, in advance, of any
         proposed variances.

         16.1.    Quantities shipped over the specified delivery quantity may be
                  returned to SELLER at SELLER'S expense.

         16.2.    The un-shipped quantities of short shipments, if not closed
                  short by the BUYER, will be considered late and subject to
                  SELLER'S liability for freight costs on the shorted
                  quantities.


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998


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                            PURCHASE AGREEMENT #10152


17.      NON-CONFORMING MATERIALS:

         17.1.    The products delivered by SELLER may be inspected and tested
                  as required by the BUYER. If BUYER determines that materials
                  received do not meet the specifications to which they were
                  ordered or are defective in material or workmanship, BUYER may
                  return the materials to SELLER at SELLER'S expense for rework
                  or replacement. SELLER shall provide BUYER with a Return
                  Authorization (RA) Number within 24 hours of BUYER'S request.
                  SELLER must then repair, replace or credit BUYER'S account for
                  said items as determined by mutual agreement of both parties.
                  Repair or replacement of non-conforming assemblies is to be
                  done within one week from the date non-conforming materials is
                  received by SELLER at the manufacturing site. SELLER must also
                  provide a report to BUYER detailing the cause of the
                  non-conformance and corrective action taken to assure it will
                  not happen again.

         17.2.    Non-conforming material situations may be negotiated by the
                  BUYER to ensure that BUYER'S production requirements are
                  attained with Seller reserving first right of refusal to
                  remedy. This may include, back-charging SELLER for rework and
                  sorting costs when return of materials to SELLER does not meet
                  BUYER'S business needs. Back-charge costs will be agreed upon
                  by SELLER and the BUYER, prior to performing the rework or
                  sorting.

         17.3.    Other SELLER'S facilities can be used to perform the rework,
                  if required, to meet BUYER'S production requirements. There
                  will be no additional freight or rework charges to the BUYER.

         17.4.    Component infant mortality or components that fail not due to
                  workmanship at BUYER'S facility shall not be the
                  responsibility of the SELLER. Any repair or rework desired by
                  the BUYER shall be billed at a standard hourly rate as
                  established by the SELLER.

18.      PAYMENT METHOD AND TERMS:

         18.1.    PAYMENT METHOD: All payments will be made in US Dollars.

         18.2.    PAYMENT TERMS: Net 30 days from invoice date.

19.      CUSTOM TOOLING PURCHASES:

         19.1.    DEFINITION: Custom tooling shall be defined to include all
                  related hardware, software and supporting design documentation
                  unique or dedicated to BUYER'S requirements.

         19.2.    OWNERSHIP: Unless specifically noted on the purchase order or
                  tooling agreement document:

                  19.2.1.  Tooling purchased or paid for by BUYER shall become
                           the property of BUYER and must be returned to BUYER
                           upon request. BUYER will be responsible for packaging
                           and shipping cost for relocating BUYER tooling and
                           equipment from SELLER's facility. Any equipment
                           consigned or paid for by BUYER is to be used solely
                           for the purpose for which it was designed and used
                           only for BUYER'S assemblies. Calibration of all
                           SELLER owned/operated equipment and BUYER consigned
                           equipment must be traceable to ISO 9002 requirements
                           where applicable.

                  19.2.2.  RETURN OF TOOLING TO BUYER (if so requested by BUYER)

                           19.2.2.1. Tooling to be returned to BUYER upon
                                     BUYER'S written request within 15 days of
                                     last lot completed needing the use of the
                                     tool.

                  19.2.3.  MARKING OF TOOLING: Tooling paid for by BUYER must be
                           permanently marked, if practical, with "PROPERTY OF
                           CIELO COMMUNICATIONS, INC".

         19.3.    IN-CIRCUIT TEST (ICT)

                  19.3.1.  New Programs: SELLER will quote the necessary ICT
                           fixturing and other NRE charges on new assemblies and
                           provide an itemized list of charges in the initial
                           quotation.

         Ongoing Support: Repair and maintenance shall be the responsibility of
         the SELLER unless replacement is necessary as deemed by BUYER and
         SELLER at which time BUYER shall provide a purchase order for
         replacement of the fixture. Changes to the design causing said tooling
         to change shall be the responsibility of the BUYER.

                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998
<PAGE>   6


                            PURCHASE AGREEMENT #10152


         19.4     FUNCTIONAL CIRCUIT TEST (FCT)

                  19.4.1   New Program: SELLER will quote the cost of design and
                           development of FCT and provide an itemized list, or
                           BUYER will supply SELLER with necessary equipment and
                           documentation to perform FCT.

                  19.4.2   Ongoing Support: All charges associated with
                           repair/replacement of custom or BUYER supplied
                           equipment is the responsibility of the BUYER. SELLER
                           will ask for purchase orders to cover these charges
                           or BUYER will provide replacement parts.

         19.5     Other: All charges related to repair/replacing custom tooling
                  that is unique to the BUYER'S requirements is the
                  responsibility of the BUYER. SELLER will ask for purchase
                  orders to cover these charges or BUYER will provide
                  replacement parts.

         19.6     PREVENTATIVE MAINTENANCE AND CALIBRATION: SELLER to provide
                  preventive maintenance and calibration on all equipment
                  consigned by BUYER per ISO 9002 requirements. Preventative
                  maintenance and calibration costs on all BUYER supplied
                  equipment or custom equipment procured by SELLER and paid for
                  by BUYER is the responsibility of the BUYER. SELLER agrees to
                  work with the BUYER to determine preventative maintenance and
                  calibration schedule on equipment.

         19.7     TOOLING CARE: Normal care of tooling shall be borne by SELLER.

         19.8     TOOLING REPORT: At a minimum of every 6 months, SELLER will
                  provide BUYER with a report which provides the tooling owned
                  by BUYER and its condition.

         19.9     END OF LIFE: Tooling which has reached the end of its useful
                  life and idle tooling will be retained by SELLER until BUYER
                  provides written disposition to SELLER.

         19.10    BUYER is responsible for freight costs, taxes, duties
                  calibration, preventive maintenance, or other similar costs
                  related to BUYER purchased / supplied tooling only.

20.      SELLER'S MANUFACTURING PROCESS: Both BUYER and SELLER agree to pursue
         continuous improvement in all areas of their businesses, including the
         SELLER'S manufacturing processes.

         20.1     Manufacturing process changes which can significantly affect
                  the quality, performance and/or cost of the product being
                  purchased are to be reviewed and approved by BUYER before
                  implementation by SELLER.

         20.2     Manufacturing process changes which SELLER believes will have
                  no impact upon the quality, performance and/or cost of the
                  product being purchased may be implemented at the discretion
                  of SELLER with notification to the BUYER. SELLER will remain
                  fully responsible for meeting product specification and
                  usability requirements.

21.      SUPPLIER DEVELOPMENT PROGRAM: SELLER agrees to actively participate
         with BUYER in BUYER'S Supplier Development Program.

         21.1     FORMAL QUARTERLY REVIEW: As part of the Supplier Development
                  Program, BUYER and SELLER agree to alternate hosting of Formal
                  Quarterly Meetings. The following representatives should
                  attend at a minimum:

                  Management - BUYER and SELLER

                  Program Manager - SELLER

                  Commodity Manager - BUYER

         The agenda is noted in Schedule B.

22.      MISCELLANEOUS TERMS AND CONDITIONS:

         22.1     All terms and conditions will be per the terms and conditions
                  found in this Agreement. If any difference exists between the
                  terms and conditions of the purchase orders and this
                  Agreement, the terms and conditions of this Agreement will
                  take precedence.


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998


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                            PURCHASE AGREEMENT #10152

         22.2     All issues, disputes and particular items which arise and
                  which are not specifically addressed in this Agreement and/or
                  the individual BUYER purchase orders will be discussed and
                  resolved through good faith negotiations.

23.      CONTRACT TERMINATION:

         23.1     This Agreement may be terminated by BUYER within 180 days
                  written notice of breach of this agreement, provided SELLER
                  has not cured said breach within 60 days of receipt of breach.
                  Voiding of this agreement shall not relieve BUYER of its
                  obligation to pay for finished goods or raw materials which
                  have been ordered or delivered, as defined in Section 7, and
                  shall not relieve SELLER of any liabilities incurred during
                  the term of this Agreement, including, without limitation, any
                  liability of SELLER for breach of this Agreement and any
                  liability of SELLER for warranty obligation on the terms of
                  this Agreement.

         23.2     This Agreement may be terminated for cause by SELLER upon 180
                  days written notice of breach of this agreement, provided
                  BUYER has not cured said breach within 60 days of receipt of
                  breach Voiding of this Agreement shall not relieve BUYER of
                  its obligation to settle all outstanding sums due and payable
                  for finished goods or raw materials which have been ordered or
                  delivered, as defined in Section 7, and for any other
                  liabilities incurred during the term of this Agreement. Nor
                  shall it relieve SELLER of any liabilities incurred during the
                  term of this Agreement, including, without limitation, any
                  liability of SELLER for breach of this Agreement and any
                  liability of SELLER for warranty obligation on the terms of
                  this Agreement.

         23.3     SELLER or BUYER may terminate this Agreement without cause
                  upon six (6) months written notice. In the event of such
                  termination the parties shall mutually agree on the phase out
                  plan.

         23.4     Survival of Certain Provisions: Notwithstanding anything to
                  the contrary in this Agreement, the following sections shall
                  survive termination of this Agreement: 17, 18, 19, 22, 26, 27,
                  28 and 29.

24.      FORCE MAJEURE: No party will be liable to the other parties for its
         failure to perform or for delay in the performance of its obligations
         under this Agreement to the extent such failure or delay results from
         causes beyond its reasonable control, including, without limitation,
         acts of God, fires, explosions, wars or other hostilities,
         insurrections, revolutions, earthquakes, floods, epidemics or
         quarantine restrictions, unforeseeable governmental restrictions or
         controls, or transportation embargoes or interruptions; provided,
         however, that if a party is prevented from performing its obligations
         under this Agreement because of such extraordinary circumstances for a
         period of 10 consecutive days, the other parties may terminate this
         Agreement immediately upon notice to the other parties.

25.      CONTINGENCY PLAN: SELLER to provide BUYER a mutually acceptable
         disaster recovery plan within 3 months of signing this agreement. Upon
         approval of the disaster recovery plan by BUYER, the document will be
         added to this agreement.

26.      INDEMNIFICATION: Each party warrants to the other that it has full
         right, power, legal capacity and authority to enter into and perform
         this Agreement and that it will indemnify and hold harmless the other
         party for any breach of this warranty.

         26.1     Indemnification by SELLER: SELLER agrees, at its own expense
                  to indemnify the BUYER against any damages, costs (including
                  attorneys' fees and costs) or other liability arising from any
                  claim brought against them with respect to any products
                  manufactured by SELLER, (collectively "BUYERS Losses") to the
                  extent such BUYER Losses are caused by SELLER's failure to
                  manufacturer the Products in conformance with the
                  Specifications and with SELLER's warranties as set forth in
                  this Agreement, or by SELLERS's misconduct or negligence;
                  provided, with respect to any claim or action, that BUYER
                  provides (i) prompt written notice of such claim or action,
                  (ii) sole control and authority over the defense or settlement
                  of such claim or action and (iii) proper and full information
                  and reasonable assistance to defend and/or settle any such
                  claim or action.

         26.2     Notwithstanding anything to the contrary herein, neither party
                  nor its agent(s), representative(s) or employee(s) shall be
                  liable to the other pursuant to this agreement for amounts
                  representing loss of revenues, loss of profits, loss of
                  business or indirect, consequential, special or punitive
                  damages of the other party, however caused and on any theory
                  of liability, even if the other party has been advised of the
                  possibility of such damages. The liability of the BUYER, its
                  agent(s)


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998
<PAGE>   8


                            PURCHASE AGREEMENT #10152


                  representative(s) and employee(s) to SELLER for damages or
                  alleged damages whether in contract or tort (including strict
                  liability and negligence) with respect to this agreement is
                  limited to and shall not exceed the amounts paid by BUYER to
                  SELLER under this agreement during the twelve (12) months
                  immediately preceding the event and/or Product giving rise to
                  the damages.

27.      WARRANTY: Should SELLER'S product(s) be confirmed as being faulty due
         to a defect in workmanship or fail to meet the mutually agreed upon
         specifications in effect on the date of sale within one year of
         shipment to BUYER or its customer, SELLER will repair or replace these
         faulty goods free of cost, if returned to SELLER within thirty days
         after the end of the warranty period. Goods returned after this period
         will be repaired or replaced for a charge to be negotiated. For any
         material BUYER deems necessary to have repaired or replaced at its or
         its customer's facility due faulty workmanship, SELLER shall have the
         first right of refusal to send or supply the necessary resources to
         remedy the situation in a timely manner as mutually agreed between the
         two parties.

28.      CONFIDENTIAL INFORMATION

         28.1     Nondisclosure and Nonuse: Each party shall treat as
                  confidential all Confidential Information of the other party,
                  shall not use such Confidential Information except as set
                  forth in this Agreement, and shall use reasonable efforts not
                  to disclose such Confidential Information to any third party.
                  Each party shall disclose Confidential Information of the
                  other party only to its directors, officers, employees, and
                  consultants who are required to have such information in order
                  for such party to carry out the transactions contemplated by
                  this Agreement and who have signed nondisclosure agreements
                  protecting the Confidential Information on substantially the
                  same terms as this Agreement. Each party shall promptly notify
                  the other party of any actual or suspected misuse or
                  unauthorized disclosure of the other party's Confidential
                  Information.

         28.2     Exceptions: Notwithstanding the above, neither party shall
                  have liability to the other with regard to any Confidential
                  Information of the other which the receiving party can prove:
                  (i) was in the public domain at the time it was disclosed or
                  has entered the public domain through no fault of the
                  receiving party; (ii) was known to the receiving party,
                  without restriction at the time of disclosure as demonstrated
                  by files in existence at the time of disclosure; (iii) is
                  disclosed with the prior written approval of the disclosing
                  party; (iv) becomes known to the receiving party without
                  restriction from a source other than the disclosing party
                  without breach of this Agreement by the receiving party and
                  otherwise not in violation of the disclosing party's rights;
                  (v) is disclosed generally to third parties by the disclosing
                  party without restrictions similar to those contained in this
                  Agreement; (vi) is disclosed pursuant to the order or
                  requirement of a court, administrative agency, or other
                  governmental body; provided however that the receiving party
                  shall provide prompt notice of such court order or requirement
                  to the disclosing party to enable the disclosing party to seek
                  a protective order or otherwise prevent or restrict
                  disclosure.

         28.3     Return of Confidential Information: Upon expiration of this
                  Agreement, each party shall promptly return all Confidential
                  Information of the other party.

         28.4     Remedies: Any breach of the restrictions contained in this
                  Section 28 is a breach of this Agreement which may cause
                  irreparable harm to the nonbreaching party. Any such breach
                  shall entitle the nonbreaching party to injunctive relief in
                  addition to all legal remedies.

         28.5     "Confidential Information" of a party shall mean any
                  information disclosed by that party to the other pursuant to
                  this Agreement which is written, graphic, machine readable or
                  other tangible form and is marked "Confidential",
                  "Proprietary" or in some other manner to indicate its
                  confidential nature. Confidential Information may also include
                  oral information disclosed by one party to the other pursuant
                  to this Agreement, provided that such information is
                  designated as confidential at the time of disclosure and is
                  reduced to writing by the disclosing party within thirty (30)
                  days after its oral disclosure, and such writing is marked in
                  a manner to indicate its confidential nature and delivered to
                  the receiving party.


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998


<PAGE>   9


                            PURCHASE AGREEMENT #10152


29.      MISCELLANEOUS


         29.1     Amendments and Waivers: Any term of this Agreement may be
                  amended or waived only with the written consent of the parties
                  or their respective successors and assigns. Any amendment or
                  waiver effected in accordance with this Section 29.1 shall be
                  binding upon the parties and their respective successors and
                  assigns.

         29.2     Successors and Assigns: SELLER shall not assign any of its
                  rights, obligations or privileges (by operation of law or
                  otherwise) hereunder without the prior written consent of
                  BUYER. BUYER shall have the right to assign its rights,
                  obligations and privileges hereunder to an assignee that
                  agrees in writing to be bound by the terms of this Agreement.
                  Subject to the foregoing, the terms and conditions of this
                  Agreement shall inure to the benefit of and be binding upon
                  the respective permitted successors and assigns of the
                  parties.

         29.3     Governing Law; Jurisdiction: This Agreement and all acts and
                  transactions pursuant hereto and the rights and obligations of
                  the parities hereto shall be governed, construed and
                  interpreted in accordance with the laws of the State of
                  Colorado without giving effect to principles of conflicts of
                  law.

         29.4     Notices: Any notice required or permitted by this Agreement
                  shall be in writing and shall be deemed sufficient upon
                  receipt, when delivered personally or by courier, overnight
                  delivery service or confirmed facsimile, or forty-eight (48)
                  hours after being deposited in the regular mail as certified
                  or registered mail (airmail if sent internationally) with
                  postage prepaid if such notice is addressed to the party to be
                  notified at such party's address or facsimile number as set
                  forth, or subsequently modified by written notice.

         29.5     Severability: If one or more provisions of this Agreement are
                  held to be unenforceable under applicable law, the parties
                  agree to renegotiate such provision in good faith, in order to
                  maintain the economic position enjoyed by each party as close
                  as possible to that under the provision rendered
                  unenforceable. In the event that the parties cannot reach a
                  mutually agreeable and enforceable replacement for such
                  provision, then (i) such provision shall be excluded from this
                  Agreement, (ii) the balance of the Agreement shall be
                  interpreted as if such provision were so excluded and (iii)
                  the balance of the Agreement shall be enforceable in
                  accordance with its terms.

         29.6     Entire Agreement: This agreement and the documents referred to
                  herein are the product of both parties hereto, and constitute
                  the entire Agreement between such parties pertaining to the
                  subject matter hereof and thereof, and merge all prior
                  negotiations and drafts of the parties with regard to the
                  transactions contemplated herein and therein. Any and all
                  other written or oral agreements existing between the parties
                  hereto regarding such transactions are expressly cancelled.

         29.7     Independent Contractors: The relationship of SELLER and BUYER
                  established by this Agreement is that of independent
                  contractors, and nothing contained in this Agreement will be
                  construed (i) to give either party the power to direct and
                  control the day-to-day activities of the other (ii) to
                  construe the parties as partners, joint ventures, co-owners or
                  otherwise as participants in a joint or common undertaking, or
                  (iii) to allow either party to create ore assume any
                  obligation on behalf of the other for any purpose whatsoever.

Please acknowledge receipt and acceptance of this Agreement by signing below:

BY SELLER:   /s/ BILL PETEN               BY BUYER:   /s/ TIM BOUR
             --------------------------               -------------------------
PRINT NAME:  Bill Peten                   PRINT NAME: Tim Bour
             --------------------------               -------------------------
TITLE:       VP Materials                 TITLE:      President & CEO
             --------------------------               -------------------------
COMPANY      XeTel, Corp.                 COMPANY     Cielo Communications. Inc.
             --------------------------               -------------------------
DATE:        6/2/98                       DATE:       6/4/98
             --------------------------               -------------------------


                                                       Purchase Agreement #10152
                                                                          Rev. A
                                                                    June 1, 1998
<PAGE>   10

                                   SCHEDULE A
                            PURCHASE AGREEMENT ITEMS

<TABLE>
<CAPTION>
                                          MATERIAL  ASSEMBLY   TEST             ANNUAL
PART NUMBER       DESCRIPTION               COST      COST     COST    PROFIT    QTY     KANBAN SIZE
-----------   -----------------------     --------  --------   ----    ------   ------   -----------
<S>           <C>                         <C>       <C>        <C>     <C>      <C>      <C>
30-2020-701   FC1063SW-GBIC-Untested

30-2020-751   FC1063SW-GBIC-Tested

30-2028-701   GBE1250SW-GBIC-Untested

30-2028-751   GBE1250SW-GBIC-Tested
</TABLE>

BUYER:                                       SELLER:


-----------------------------------          -----------------------------------
David L. Rechberger,           Date          Tracee Casarez,                Date
Sr. Supply Engineer Manager                  Program Manager



                                                       Purchase Agreement #10152
                                                          Schedule A, Revision A
                                                                    June 1, 1998
<PAGE>   11

                                   SCHEDULE B
                                QUARTERLY REVIEW


<TABLE>
<CAPTION>
                    XeTel Responsibility                                        Cielo Responsibility
<S>                                                         <C>

                                            BUSINESS PLANS/STRATEGIES
---------------------------------------------------------------------------------------------------------------

o    Sales                                                  o    Sales
o    Business Climate                                       o    Business Climate
o    Product/Customer Mix                                   o    Product/Customer Mix
o    Expansion Plans                                        o    Expansion Plans
o    Organization Charts/Changes                            o    Organization Charts/Changes
o    Product line Updates                                   o    Product line Updates
o    New Programs                                           o    New Programs
o    Supplier Development Program                           o    Supplier Development Program

                                                 PROCESS UPDATES
---------------------------------------------------------------------------------------------------------------

o    Cost Reductions                                        o    Forecast Accuracy
o    Safety Stock Program                                   o    Payment of Invoices
o    Procurement (availability, pricing)                    o    Information Exchange - EDI
o    Receiving Inspection
o    Manufacturing Process
o    Lead Time Reduction
o    Test (ICT, FCT, Burn-In)
o    Shipping
o    Open ADR/SCAR
o    Finished Goods Safety Stock

                                                    MEASURES
---------------------------------------------------------------------------------------------------------------

o    Receiving Inspection                                   o    Incoming Receiving Inspection
     -    Overall Lot Acceptance of Components                   -    Delivery Performance
     -    PWB Lot Acceptance by assembly                         -    Delivery Performance, last 4 quarters
     -    PWB Defect Pareto by assembly                          -    PWA Lot Acceptance, last 4 quarters
     -    Supplier Quality Performance                           -    PWA Defect Pareto by Product Line, last 4
o    In Process Verification                                          quarters (top 5 defects only)
     -    As needed to identify trend
o    ICT
     -    1st Pass ICT Yield by PWA, last 6 months
     -    ICT Defect Pareto by PWA, last 6 months
          (top 5 defects only)
o    FCT
     -    1st Pass Functional Yield by PWA, last 6 months
     -    Functional Defect Pareto by PWA, last 6 months
          (top 5 defects only)
o    Final QA
     -    Final QA Yield by PWA
     -    Final QA Defect Pareto by PWA (top 5 defects
          only)
     -    Delivery Performance (Service Level)
o    Miscellaneous
     -    % Scrap at Assembly Level by PWA
     -    Failure Analysis Results on Failed Components
     -    Failure Report Updated
     -    Cumulative First Pass Yield
     -    Total annual forecasted materials expenditures
     -    FG Inventory Aging Report
</TABLE>


BUYER:                                       SELLER:


/s/ DAVID L. RECHBERGER       6/3/98         /s/ TRACEE CASAREZ       6/2/98
------------------------------------         -------------------------------
David L. Rechberger,          Date           Tracee Casarez,          Date
Sr. Supply Engineer                          Program Manager


                                                       Purchase Agreement #10152
                                                          Schedule B, Revision A
                                                                    June 1, 1998

<PAGE>   12
                                   SCHEDULE D
                              ESCALATION SCHEDULE

<TABLE>
<CAPTION>
                                                                                             Expected
                                                                                             Time for
                         Event or Action                                 Critical Level    Notification
                         ---------------                                 --------------    ------------
<S>                                                                      <C>               <C>
Change in component lead time affecting potential safety stock levels         3,4           72 hrs

Change in pricing affecting PCBA price                                        2,3,4         72 hrs

End of life notification                                                      2,3,4         72 hrs

Report of lot failure by manufacturing                                        3,4           24 hrs

Report of tool/equipment failure requiring action by Cielo                    3,4           24 hrs

Notification of contract breach or termination date by Xetel                  1,2,3,4       24 hrs

Notification of contract breach or termination date by Cielo                  1,2,3,4       24 hrs

List of component parts whose qty are below minimum level                     2,3,4         5 days

List of component parts whose qty exceeds maximum level                       3,4           5 days

Change in personnel critical to Cielo system or process                       1,2,3,4       3 days

Lack of requested response by Cielo                                           1,2,3,4       1= 30-day late
                                                                                            2= 15 day late
                                                                                            3= 10 day late
                                                                                            4= 5 day late

Lack of requested response by Xetel                                           1,2,3,4       1= 30-day late
                                                                                            2= 15 day late
                                                                                            3= 10 day late
                                                                                            4= 5 day late

Lack of response to Corrective Action Request                                 1,2,3,4       1= 30-day late
                                                                                            2= 15 day late
                                                                                            3= 10 day late
                                                                                            4= 5 day late

Failure to execute MRP by EMR Cielo                                           3,4           24 hrs
Line down not affecting delivery of needed PCBA's                             2,3,4         24 hrs
Line down affecting delivery of needed PCBA's                                 1,2,3,4       2 hrs

</TABLE>

<TABLE>
<CAPTION>
LEVEL          CIELO                   XETEL                          SUPPLIER
-----          -----                   -----                          --------
<S>       <C>                     <C>                             <C>
  1       President/CEO           President/CEO                   President/CEO
          VP Sales/Marketing      VP Operations                   VP Operations
          VP Operations           VP Sales/Marketing              VP Sales/Marketing
          Commodity Manager       VP Materials                    VP Materials
          Buyer/Planner           Program Management Director     General Manager
          Buyer/Planner           Program Manager                 General Manager
                                  Materials Coordinator           Account Manager
                                                                  Product Manager
                                                                  In-Plant Operator

  2       VP Operations           VP of Materials                 General Manager
          Buyer/Planner           Program Management Director     General Manager
          Commodity Manager       Program Manager                 Product Manager
          Buyer/Planner           Materials Coordinator           Account Manager
                                                                  In-Plant Operator

  3       Commodity Manager       Program Manager                 Product Manager
          Buyer/Planner           Materials Coordinator           Account Manager
                                                                  In-Plant Operator

  4       Buyer/Planner           Materials Coordinator           Account Manager
                                                                  In-Plant Operator
</TABLE>


BUYER:                                       SELLER:

/s/ DAVID L. RECHBERGER      6/3/98          /s/ TRACEE CASAREZ           6/2/98
-----------------------------------          -----------------------------------
David L. Rechberger,           Date          Tracee Casarez,                Date
Sr. Supply Engineer                          Program Manager



                                                       Purchase Agreement #10152
                                                          Schedule D, Revision A
                                                                    June 1, 1998
<PAGE>   13
                    MATERIALS ACQUISITION SERVICE (MAS) FEE



The MAS rate is inclusive of all costs including freight. MAS rate is subject
to further adjustments based on the total annual agreed upon forecasted volume
of unit assemblies for the next four quarters based on the following Table:

<TABLE>
<CAPTION>
Total Annual Forecasted Material                      Material Acquisition Service Fee
 Expenditures (Millions of $)                                  OSAs & Overall
================================                      ================================
<S>                                                   <C>
   Optical Sub-assemblies**                                          3%
               1                                                     15%
             2 - 3                                                  6.0%
             3 - 5                                                  5.8%
             5 - 10                                                 5.75%
            10 - 15                                                 5.5%
            15 - 20                                                 4.5%
            20 - 25                                                 4.0%
              25+                                                   3.5%
</TABLE>

The MAS fee will be calculated by multiplying the appropriate MAS percentage
based on the total material expenditure level times the total value of the
materials provided by SELLER excluding chemicals/supplies and packaging of any
given assembly.




<TABLE>
<S>                                                            <C>
BUYER:                                                         SELLER:

/s/ DAVE RECHBERGER                    6/3/98                  /s/ TRACEE CASAREZ                   6/2/98
-----------------------------------------------                --------------------------------------------
Dave Rechberger - Sr. Supply Engineer   Date                   Tracee Casarez - Program Manager      Date
</TABLE>




                                                       Purchase Agreement #10152
                                                          Schedule E, Revision A
                                                                    June 1, 1998