Exhibit 10.66
 
REGISTRATION RIGHTS AGREEMENT

This Registration Rights Agreement (the “Agreement”) is made and entered into as
of March 10, 2008 by and among Modtech Holdings, Inc., a Delaware corporation
(the “Company”), and the “Buyers” named in that certain Subscription Agreement
by and among the Company and the Buyers, dated the date hereof (the
“Subscription Agreement”). Capitalized terms used herein have the respective
meanings ascribed thereto in the Subscription Agreement unless otherwise defined
herein.
 
The parties hereby agree as follows:
 
1. Certain Definitions.
 
As used in this Agreement, the following terms shall have the following
meanings:
 
“Buyers” shall mean the Buyers identified in the Subscription Agreement and any
Affiliate or permitted transferee of any Buyer who is a subsequent holder of any
Registrable Securities.
 
“Common Stock” shall mean the Company’s common stock, par value $0.01 per share,
and any securities into which such shares may hereinafter be reclassified.
 
“Insider” means a Person who is either an officer or a director of the Company
or any Subsidiary of the Company.
 
“Insider Shares” means the Shares purchased by any Insider.
 
“Prospectus” shall mean (i) the prospectus included in any Registration
Statement, as amended or supplemented by any prospectus supplement, with respect
to the terms of the offering of any portion of the Registrable Securities
covered by such Registration Statement and by all other amendments and
supplements to the prospectus, including post-effective amendments and all
material incorporated by reference in such prospectus, and (ii) any “free
writing prospectus” as defined in Rule 405 under the 1933 Act.
 
“Register,” “registered” and “registration” refer to a registration made by
preparing and filing a Registration Statement or similar document in compliance
with the 1933 Act (as defined below), and the declaration or ordering of
effectiveness of such Registration Statement or document.
 
“Registrable Securities” shall mean (i) the Shares and (ii) any other securities
issued or issuable with respect to or in exchange for Registrable Securities;
provided, that, a security shall cease to be a Registrable Security upon (A)
sale pursuant to a Registration Statement or Rule 144 under the 1933 Act, or (B)
such security becoming eligible for sale without restriction by the Buyers
pursuant to Rule 144.
 
“Registration Statement” shall mean any registration statement of the Company
filed under the 1933 Act that covers the resale of any of the Registrable
Securities pursuant to the provisions of this Agreement, amendments and
supplements to such Registration Statement, including post-effective amendments,
all exhibits and all material incorporated by reference in such Registration
Statement.
 

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“Required Buyers” means the Buyers holding a majority of the Registrable
Securities.
 
“SEC” means the U.S. Securities and Exchange Commission.
 
“Shares” means the shares of Common Stock to be issued upon conversion of the
Series B Preferred Stock and Series C Preferred Stock issued pursuant to the
Subscription Agreement.
 
 “1933 Act” means the Securities Act of 1933, as amended, and the rules and
regulations promulgated thereunder.
 
“1934 Act” means the Securities Exchange Act of 1934, as amended, and the rules
and regulations promulgated thereunder.
 
2. Registration.
 
(a)  Registration Statements.
 
(i) Promptly following the Closing but no later than the earlier of (i) Five (5)
Business Days after the Company files its Annual Report on Form 10-K for the
year ended December 31, 2007 with the SEC or (ii) April 7, 2008 (the “Filing
Deadline”), the Company shall prepare and file with the SEC one Registration
Statement on Form S-3 (or, if Form S-3 is not then available to the Company, on
such form of registration statement as is then available to effect a
registration for resale of the Registrable Securities), covering the resale of
the Shares (the “Registrable Securities”). Subject to any SEC comments, such
Registration Statement shall include the plan of distribution attached hereto as
Exhibit A; provided, however, that no Buyer shall be named as an “underwriter”
in the Registration Statement without the Buyer's ' prior written consent. Such
Registration Statement also shall cover, to the extent allowable under the 1933
Act and the rules promulgated thereunder (including Rule 416), such
indeterminate number of additional shares of Common Stock resulting from stock
splits, stock dividends or similar transactions with respect to the Registrable
Securities. Such Registration Statement shall not include any shares of Common
Stock or other securities for the account of any other holder without the prior
written consent of the Required Buyers; provided, however, that the Company may
include in such Registration Statement the securities defined as "Registrable
Securities" under the Registration Rights Agreements dated February 29, 2008
between the Company and Laurus Master Fund, Ltd., Valens Offshore SPV I, Ltd.,
and Valens U.S. SPV I, LLC (the "Other Registrable Securities"). The
Registration Statement (and each amendment or supplement thereto, and each
request for acceleration of effectiveness thereof) shall be provided in
accordance with Section 3(c) to the Buyers prior to its filing or other
submission. If a Registration Statement covering the Registrable Securities is
not filed with the SEC on or prior to the Filing Deadline, the Company will make
pro rata payments to each Buyer (other than an Insider), as liquidated damages
and not as a penalty, in an amount equal to 1.5% of the aggregate amount
invested by such Buyer on the Closing Date for each 30-day period or pro rata
for any portion thereof following the Filing Deadline for which no Registration
Statement is filed with respect to the Registrable Securities. Such payments
shall constitute the Buyers' exclusive monetary remedy for such events, but
shall not affect the right of the Buyers to seek injunctive relief. Such
payments shall be made to each Buyer in cash within three Business Days after
the end of each calendar month.
 
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(b)  Expenses. The Company will pay all expenses associated with each
registration, including filing and printing fees, the Company’s counsel and
accounting fees and expenses, costs associated with clearing the Registrable
Securities for sale under applicable state securities laws, listing fees, fees
in connection with the registration, but excluding discounts, commissions, fees
of underwriters, selling brokers, dealer managers or similar securities industry
professionals with respect to the Registrable Securities being sold.
 
(c)  Effectiveness.
 
(i) The Company shall use commercially reasonable efforts to have any
Registration Statement declared effective as soon as practicable. The Company
shall notify the Buyers by facsimile or e-mail as promptly as practicable, and
in any event, within twenty-four (24) hours, after any Registration Statement is
declared effective and shall simultaneously provide the Buyers with copies of
any related Prospectus to be used in connection with the sale or other
disposition of the securities covered thereby. If (A)(x) a Registration
Statement covering the Registrable Securities is not declared effective by the
SEC prior to the earlier of (i) five (5) Business Days after the SEC shall have
informed the Company that no review of the Registration Statement will be made
or that the SEC has no further comments on the Registration Statement or (ii)
the 60th day after the Filing Deadline or (B) after a Registration Statement has
been declared effective by the SEC, sales cannot be made pursuant to such
Registration Statement for any reason (including without limitation by reason of
a stop order, or the Company’s failure to update the Registration Statement),
but excluding any Allowed Delay (as defined below) or the inability of any Buyer
to sell the Registrable Securities covered thereby due to market conditions,
then, if a Buyer cannot sell their Registrable Securities without restriction
pursuant to Rule 144 or otherwise, the Company will make pro rata payments to
each such Buyer (other than an Insider) as liquidated damages and not as a
penalty, in an amount equal to 1.5% of the aggregate amount invested by such
Buyer under the Subscription Agreement for each 30-day period or pro rata for
any portion thereof following the date by which such Registration Statement
should have been effective (the “Blackout Period”). Such payments shall
constitute the Buyers' exclusive monetary remedy for such events, but shall not
affect the right of the Buyers to seek injunctive relief. The amounts payable as
liquidated damages pursuant to this paragraph shall be paid monthly within three
(3) Business Days of the last day of each month following the commencement of
the Blackout Period until the termination of the Blackout Period. Such payments
shall be made to each Buyer in cash.
 
(ii) For not more than twenty (20) consecutive days or for a total of not more
than forty-five (45) days in any twelve (12) month period, the Company may
suspend the use of any Prospectus included in any Registration Statement
contemplated by this Section in the event that the Company determines in good
faith that such suspension is necessary to (A) delay the disclosure of material
non-public information concerning the Company, the disclosure of which at the
time is not, in the good faith opinion of the Company, in the best interests of
the Company or (B) amend or supplement the affected Registration Statement or
the related Prospectus so that such Registration Statement or Prospectus shall
not include an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein,
in the case of the Prospectus in light of the circumstances under which they
were made, not misleading (an “Allowed Delay”); provided, that the Company shall
promptly (a) notify each Buyer in writing of the commencement of and the reasons
for an Allowed Delay, but shall not (without the prior written consent of a
Buyer other than an Insider) disclose to such Buyer any material non-public
information giving rise to an Allowed Delay, (b) advise the Buyers in writing to
cease all sales under the Registration Statement until the end of the Allowed
Delay and (c) use commercially reasonable efforts to terminate an Allowed Delay
as promptly as practicable.

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(d) Rule 415; Cutbacks. If at any time the SEC takes the position that the
offering of some or all of the Registrable Securities or the Other Registrable
Securities in a Registration Statement is not eligible to be made on a delayed
or continuous basis under the provisions of Rule 415 under the 1933 Act or
requires any Buyer to be named as an “underwriter”, the Company shall use its
commercially reasonable best efforts to persuade the SEC that the offering
contemplated by the Registration Statement is a valid secondary offering and not
an offering “by or on behalf of the issuer” as defined in Rule 415 and that none
of the Buyers is an “underwriter”. The Buyers collectively (other than the
Insiders) shall have the right to each have a single counsel representing them
participate in any meetings or discussions with the SEC regarding the SEC’s
position and to have their counsel comment on any written submission made to the
SEC with respect thereto. No such written submission shall be made to the SEC to
which the Buyers' counsel reasonably objects. In the event that, despite the
Company’s commercially reasonable efforts and compliance with the terms of this
Section 2(e), the SEC refuses to alter its position, the Company shall (i)
remove from the Registration Statement such portion of the Registrable
Securities (the “Cut Back Shares”) and/or (ii) agree to such restrictions and
limitations on the registration and resale of the Registrable Securities as the
SEC may require to assure the Company’s compliance with the requirements of Rule
415; provided, however, that the Company shall not agree to name any Buyer as an
“underwriter” in such Registration Statement without the prior written consent
of such Buyer (collectively, the “SEC Restrictions”). Any cut-back imposed
pursuant to this Section 2(d) shall be allocated first, to the Insider Shares
pro rata among the holders thereof, and second, to the remaining Registrable
Securities held by Buyer's pro rata among them, unless the SEC Restrictions
otherwise require or provide. No liquidated damages shall accrue on or as to any
Cut Back Shares. No cut-back will be imposed on the Other Registrable
Securities.
 
3. Company Obligations. The Company will use commercially reasonable efforts to
effect the registration of the Registrable Securities in accordance with the
terms hereof, and pursuant thereto the Company will, as expeditiously as
possible:
 
(a)  use commercially reasonable efforts to cause such Registration Statement to
become effective and to remain continuously effective for a period that will
terminate upon the earlier of (i) the date on which all Registrable Securities
covered by such Registration Statement as amended from time to time, have been
sold, and (ii) the date on which all Registrable Securities covered by such
Registration Statement may be sold without restriction pursuant to Rule 144 (the
“Effectiveness Period”) and advise the Buyers writing when the Effectiveness
Period has expired. it being understood that the Effectiveness Period may expire
for some Buyers sooner than others;
 
(b)  prepare and file with the SEC such amendments and post-effective amendments
to the Registration Statement and the Prospectus as may be necessary to keep the
Registration Statement effective for the Effectiveness Period and to comply with
the provisions of the 1933 Act and the 1934 Act with respect to the distribution
of all of the Registrable Securities covered thereby;

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(c)  provide copies to and permit a single counsel designated by the Buyers to
review each Registration Statement and all amendments and supplements thereto no
fewer than three (3) Business Days prior to their filing with the SEC and not
file any document to which such counsel reasonably objects;
 
(d)  furnish to the Buyers (other than the Insiders) and the legal counsel of
the Buyers, if any (i) promptly after the same is prepared and publicly
distributed, filed with the SEC, or received by the Company (but not later than
two (2) Business Days after the filing date, receipt date or sending date, as
the case may be) one (1) copy of any Registration Statement and any amendment
thereto, each preliminary prospectus and Prospectus and each amendment or
supplement thereto, and each letter written by or on behalf of the Company to
the SEC or the staff of the SEC, and each item of correspondence from the SEC or
the staff of the SEC, in each case relating to such Registration Statement
(other than any portion of any thereof which contains information for which the
Company has sought confidential treatment), and (ii) such number of copies of a
Prospectus, including a preliminary prospectus, and all amendments and
supplements thereto and such other documents as each Buyer may reasonably
request in order to facilitate the disposition of the Registrable Securities
owned by such Buyer that are covered by the related Registration Statement;
 
(e)  use commercially reasonable efforts to (i) prevent the issuance of any stop
order or other suspension of effectiveness and, (ii) if such order is issued,
obtain the withdrawal of any such order at the earliest possible moment;
 
(f)  prior to any public offering of Registrable Securities use commercially
reasonable efforts to register or qualify or cooperate with the Buyers and their
respective counsels, if any, in connection with the registration or
qualification of such Registrable Securities for offer and sale under the
securities or blue sky laws of such jurisdictions requested by the Buyers and do
any and all other commercially reasonable acts or things necessary or advisable
to enable the distribution in such jurisdictions of the Registrable Securities
covered by the Registration Statement; provided, however, that the Company shall
not be required in connection therewith or as a condition thereto to (i) qualify
to do business in any jurisdiction where it would not otherwise be required to
qualify but for this Section 3(f), (ii) subject itself to general taxation in
any jurisdiction where it would not otherwise be so subject but for this Section
3(f), or (iii) file a general consent to service of process in any such
jurisdiction;
 
(g)  use commercially reasonable efforts to cause all Registrable Securities
covered by a Registration Statement to be listed on each securities exchange,
interdealer quotation system or other market on which similar securities issued
by the Company are then listed;
 
(h)  immediately notify the Buyers, at any time prior to the end of the
Effectiveness Period, upon discovery that, or upon the happening of any event as
a result of which, the Prospectus includes an untrue statement of a material
fact or omits to state any material fact required to be stated therein or
necessary to make the statements therein not misleading in light of the
circumstances then existing, and promptly prepare, file with the SEC and furnish
to such holder a supplement to or an amendment of such Prospectus as may be
necessary so that such Prospectus shall not include an untrue statement of a
material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein not misleading in light of the
circumstances then existing; and

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(i)  otherwise use commercially reasonable efforts to comply with all applicable
rules and regulations of the SEC under the 1933 Act and the 1934 Act, file any
final Prospectus, including any supplement or amendment thereof, with the SEC
pursuant to Rule 424 under the 1933 Act, and take such other actions as may be
reasonably necessary to facilitate the registration of the Registrable
Securities hereunder; and make available to its security holders, as soon as
reasonably practicable, but not later than the Availability Date (as defined
below), an earnings statement covering a period of at least twelve (12) months,
beginning after the effective date of each Registration Statement, which
earnings statement shall satisfy the provisions of Section 11(a) of the 1933
Act, including Rule 158 promulgated thereunder (for the purpose of this
subsection 3(i), “Availability Date” means the 45th day following the end of the
fourth fiscal quarter that includes the effective date of such Registration
Statement, except that, if such fourth fiscal quarter is the last quarter of the
Company’s fiscal year, “Availability Date” means the 90th day after the end of
such fourth fiscal quarter).
 
(j)  With a view to making available to the Buyers the benefits of Rule 144 (or
its successor rule) and any other rule or regulation of the SEC that may at any
time permit the Buyers to sell shares of Common Stock to the public without
registration, the Company covenants and agrees to: (i) make and keep public
information available, as those terms are understood and defined in Rule 144,
until the earlier of (A) six months after such date as all of the Registrable
Securities may be sold without restriction by the holders thereof pursuant to
Rule 144 or any other rule of similar effect or (B) such date as all of the
Registrable Securities shall have been resold; (ii) file with the SEC in a
timely manner all reports and other documents required of the Company under the
1934 Act; and (iii) furnish to each Buyer upon request, as long as such Buyer
owns any Registrable Securities, (A) a written statement by the Company that it
has complied with the reporting requirements of the 1934 Act, (B) a copy of the
Company’s most recent Annual Report on Form 10-K or Quarterly Report on Form
10-Q, and (C) such other information as may be reasonably requested in order to
avail such Buyer of any rule or regulation of the SEC that permits the selling
of any such Registrable Securities without registration.
 
5. Obligations of the Buyers.
 
(a)  Each Buyer shall furnish in writing to the Company such information
regarding itself, the Registrable Securities held by it and the intended method
of disposition of the Registrable Securities held by it, as shall be reasonably
required to effect the registration of such Registrable Securities and shall
execute such documents in connection with such registration as the Company may
reasonably request. At least five (5) Business Days prior to the first
anticipated filing date of any Registration Statement, the Company shall notify
each Buyer of the information the Company requires from them if they elect to
have any of the Registrable Securities included in the Registration Statement.
Each Buyer shall provide such information to the Company at least two (2)
Business Days prior to the first anticipated filing date of such Registration
Statement if they elect to have any of the Registrable Securities included in
the Registration Statement.

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(b)  Each Buyer, by their acceptance of the Registrable Securities agrees to
cooperate with the Company as reasonably requested by the Company in connection
with the preparation and filing of a Registration Statement hereunder, unless
they have notified the Company in writing of their election to exclude all of
their Registrable Securities from such Registration Statement.
 
(c)  Each Buyer agrees that, upon receipt of any notice from the Company of
either (i) the commencement of an Allowed Delay pursuant to Section 2(c)(ii) or
(ii) the happening of an event pursuant to Section 3(h) hereof, they will
immediately discontinue disposition of Registrable Securities pursuant to the
Registration Statement covering such Registrable Securities, until they are
advised by the Company that such dispositions may again be made.
 
6. Indemnification.
 
(a)  Indemnification by the Company. The Company will indemnify and hold
harmless each Buyer and their respective officers, directors, members, employees
and agents, successors and assigns, and each other person, if any, who controls
such Buyer within the meaning of the 1933 Act, against any losses, claims,
damages or liabilities, joint or several, to which they may become subject under
the 1933 Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon: (i)
any untrue statement or alleged untrue statement of any material fact contained
in any Registration Statement, any preliminary Prospectus or final Prospectus,
or any amendment or supplement thereof; (ii) any blue sky application or other
document executed by the Company specifically for that purpose or based upon
written information furnished by the Company filed in any state or other
jurisdiction in order to qualify any or all of the Registrable Securities under
the securities laws thereof (any such application, document or information
herein called a “Blue Sky Application”); (iii) the omission or alleged omission
to state in a Blue Sky Application a material fact required to be stated therein
or necessary to make the statements therein not misleading; (iv) any violation
by the Company or its agents of any rule or regulation promulgated under the
1933 Act applicable to the Company or its agents and relating to action or
inaction required of the Company in connection with such registration; or (v)
any failure to register or qualify the Registrable Securities included in any
such Registration Statement in any state where the Company or its agents has
affirmatively undertaken or agreed in writing that the Company will undertake
such registration or qualification on behalf of a Buyer and will reimburse such
Buyer, and each of their respective officers, directors or members and each of
their controlling persons for any legal or other expenses reasonably incurred by
them in connection with investigating or defending any such loss, claim, damage,
liability or action; provided, however, that the Company will not be liable in
any such case if and to the extent that any such loss, claim, damage or
liability arises out of or is based upon an untrue statement or alleged untrue
statement or omission or alleged omission so made in conformity with information
furnished by such Buyer or any such controlling person in writing specifically
for use in such Registration Statement or Prospectus.

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(b)  Indemnification by the Buyers. Each Buyer agrees, severally but not
jointly, to indemnify and hold harmless, to the fullest extent permitted by law,
the Company, its directors, officers, employees, stockholders and each person
who controls the Company (within the meaning of the 1933 Act) against any
losses, claims, damages, liabilities and expense (including reasonable attorney
fees) resulting from (x) such Buyer’s failure to deliver a Prospectus in
connection with any sales under the Registration Statement, if required, or (y)
any untrue statement of a material fact or any omission of a material fact
required to be stated in the Registration Statement or Prospectus or preliminary
Prospectus or amendment or supplement thereto or necessary to make the
statements therein not misleading, to the extent, but only to the extent that
such untrue statement or omission is contained (1) in any information furnished
in writing by such Buyer to the Company specifically for inclusion in such
Registration Statement or Prospectus or amendment or supplement thereto or (2)
in an outdated or defective Prospectus delivered by the Buyer in connection with
any sales under the Registration Statement after being notified by the Company
that the Prospectus is outdated or defective, but only if and to the extent that
following the receipt of the amended or supplemented Prospectus the misstatement
or omission giving rise to such loss, claim, damage or liability would have been
corrected. In no event shall the liability of a Buyer be greater in amount than
the dollar amount of the proceeds (net of all expense paid by such Buyer in
connection with any claim relating to this Section 6 and the amount of any
damages such Buyer has otherwise been required to pay by reason of such untrue
statement or omission) received by such Buyer upon the sale of the Registrable
Securities included in the Registration Statement giving rise to such
indemnification obligation.
 
(c)  Conduct of Indemnification Proceedings. Any person entitled to
indemnification hereunder shall (i) give prompt notice to the indemnifying party
of any claim with respect to which it seeks indemnification and (ii) permit such
indemnifying party to assume the defense of such claim with counsel reasonably
satisfactory to the indemnified party; provided that any person entitled to
indemnification hereunder shall have the right to employ separate counsel and to
participate in the defense of such claim, but the fees and expenses of such
counsel shall be at the expense of such person unless (a) the indemnifying party
has agreed to pay such fees or expenses, or (b) the indemnifying party shall
have failed to assume the defense of such claim and employ counsel reasonably
satisfactory to such person or (c) in the reasonable judgment of any such
person, based upon written advice of its counsel, a conflict of interest exists
between such person and the indemnifying party with respect to such claims (in
which case, if the person notifies the indemnifying party in writing that such
person elects to employ separate counsel at the expense of the indemnifying
party, the indemnifying party shall not have the right to assume the defense of
such claim on behalf of such person); and provided, further, that the failure of
any indemnified party to give notice as provided herein shall not relieve the
indemnifying party of its obligations hereunder, except to the extent that such
failure to give notice shall materially adversely affect the indemnifying party
in the defense of any such claim or litigation. It is understood that the
indemnifying party shall not, in connection with any proceeding in the same
jurisdiction, be liable for fees or expenses of more than one separate firm of
attorneys at any time for all such indemnified parties. No indemnifying party
will, except with the consent of the indemnified party, consent to entry of any
judgment or enter into any settlement that does not include as an unconditional
term thereof the giving by the claimant or plaintiff to such indemnified party
of a release from all liability in respect of such claim or litigation.

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(d)  Contribution. If for any reason the indemnification provided for in the
preceding paragraphs (a), (b) and (c) is unavailable to an indemnified party or
insufficient to hold it harmless, other than as expressly specified therein,
then the indemnifying party shall contribute to the amount paid or payable by
the indemnified party as a result of such loss, claim, damage or liability in
such proportion as is appropriate to reflect the relative fault of the
indemnified party and the indemnifying party, as well as any other relevant
equitable considerations. No person guilty of fraudulent misrepresentation
within the meaning of Section 11(f) of the 1933 Act shall be entitled to
contribution from any person not guilty of such fraudulent misrepresentation. In
no event shall the contribution obligation of a holder of Registrable Securities
be greater in amount than the dollar amount of the proceeds (net of all expenses
paid by such holder in connection with any claim relating to this Section 6 and
the amount of any damages such holder has otherwise been required to pay by
reason of such untrue or alleged untrue statement or omission or alleged
omission) received by it upon the sale of the Registrable Securities giving rise
to such contribution obligation.
 
7. Miscellaneous.
 
(a)  Amendments and Waivers. This Agreement may be amended only by a writing
signed by the Company and the Required Buyers. The Company may take any action
herein prohibited, or omit to perform any act herein required to be performed by
it, only if the Company shall have obtained the written consent to such
amendment, action or omission to act, of the Required Buyers.
 
(b) Notices. Unless otherwise provided, any notice required or permitted under
this Agreement shall be given in writing and shall be deemed effectively given
as hereinafter described (i) if given by personal delivery, then such notice
shall be deemed given upon such delivery, (ii) if given by telex or telecopier,
then such notice shall be deemed given upon receipt of confirmation of complete
transmittal, (iii) if given by mail, then such notice shall be deemed given upon
the earlier of (A) receipt of such notice by the recipient or (B) three days
after such notice is deposited in first class mail, postage prepaid, and (iv) if
given by an internationally recognized overnight air courier, then such notice
shall be deemed given one business day after delivery to such carrier. All
notices shall be addressed to the party to be notified at the address as
follows, or at such other address as such party may designate by ten days’
advance written notice to the other party:

If to the Company:

Modtech Holdings, Inc.
2830 Barrett Avenue
Perris, California 92571
Attention: Dennis Shogren

If to the Buyers:
 
At their addresses reflected on the books and records of the  Company.

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(c)  Assignments and Transfers by Buyers. The provisions of this Agreement shall
be binding upon and inure to the benefit of the Buyers, and their respective
successors and assigns. A Buyer may transfer or assign, in whole or from time to
time in part, to one or more persons its rights hereunder in connection with the
transfer of Registrable Securities by such Buyer to such person, provided that
such Buyer complies with all laws applicable thereto and provides written notice
of assignment to the Company promptly after such assignment is effected.
 
(d)  Assignments and Transfers by the Company. This Agreement may not be
assigned by the Company (whether by operation of law or otherwise) without the
prior written consent of the Required Buyers, provided, however, that the
Company may assign its rights and delegate its duties hereunder to any surviving
or successor corporation in connection with a merger or consolidation of the
Company with another corporation, or a sale, transfer or other disposition of
all or substantially all of the Company’s assets to another corporation, without
the prior written consent of the Required Buyers, after notice duly given by the
Company to each Buyer.
 
(e)  Benefits of the Agreement. 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. Nothing in this Agreement, express or implied, is
intended to confer upon any party other than the parties hereto or their
respective successors and assigns any rights, remedies, obligations, or
liabilities under or by reason of this Agreement, except as expressly provided
in this Agreement.
 
(f)  Counterparts; Faxes. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. This Agreement may also
be executed via facsimile, which shall be deemed an original.
 
(g)  Titles and Subtitles. The titles and subtitles used in this Agreement are
used for convenience only and are not to be considered in construing or
interpreting this Agreement.
 
(h)  Severability. Any provision of this Agreement that is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions hereof but shall be interpreted as if it were written so as
to be enforceable to the maximum extent permitted by applicable law, and any
such prohibition or unenforceability in any jurisdiction shall not invalidate or
render unenforceable such provision in any other jurisdiction. To the extent
permitted by applicable law, the parties hereby waive any provision of law which
renders any provisions hereof prohibited or unenforceable in any respect.
 
(i)  Further Assurances. The parties shall execute and deliver all such further
instruments and documents and take all such other actions as may reasonably be
required to carry out the transactions contemplated hereby and to evidence the
fulfillment of the agreements herein contained.

-10-

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(j)  Entire Agreement. This Agreement is intended by the parties as a final
expression of their agreement and intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto in respect of
the subject matter contained herein. This Agreement supersedes all prior
agreements and understandings between the parties with respect to such subject
matter.
 
(k)  Governing Law; Consent to Jurisdiction; Waiver of Jury Trial. This
Agreement shall be governed by, and construed in accordance with, the internal
laws of the State of New York without regard to the choice of law principles
thereof. Each of the parties hereto irrevocably submits to the exclusive
jurisdiction of the courts of the State of New York located in New York County
and the United States District Court for the Southern District of New York for
the purpose of any suit, action, proceeding or judgment relating to or arising
out of this Agreement and the transactions contemplated hereby. Service of
process in connection with any such suit, action or proceeding may be served on
each party hereto anywhere in the world by the same methods as are specified for
the giving of notices under this Agreement. Each of the parties hereto
irrevocably consents to the jurisdiction of any such court in any such suit,
action or proceeding and to the laying of venue in such court. Each party hereto
irrevocably waives any objection to the laying of venue of any such suit, action
or proceeding brought in such courts and irrevocably waives any claim that any
such suit, action or proceeding brought in any such court has been brought in an
inconvenient forum. EACH OF THE PARTIES HERETO WAIVES ANY RIGHT TO REQUEST A
TRIAL BY JURY IN ANY LITIGATION WITH RESPECT TO THIS AGREEMENT AND REPRESENTS
THAT COUNSEL HAS BEEN CONSULTED SPECIFICALLY AS TO THIS WAIVER.

-11-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.
 
The Company:
MODTECH HOLDINGS, INC.
     
By: 
/s/ Dennis Shogren
  Name: Dennis Shogren    Title: President and Chief Executive Officer

 
-12-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Charles McGettigan
 
Charles McGettigan

 
-13-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Robert Campbell
 
Robert Campbell

 
-14-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Stanley Gaines
 
Stanley Gaines

 
-15-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Daniel Donahoe
 
Daniel Donahoe

 
-16-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.
 

 
BUYERS:
     
/s/ Dennis Shogren
 
Dennis Shogren
     
/s/ Kenneth Cragun
 
Kenneth Cragun
     
/s/ Ronald Savona
 
Ronald Savona
     
/s/ Richard Bartolotti
 
Richard Bartolotti
     
/s/ Harold Clark
 
Harold Clark
     
/s/ Karen Andreasen
 
Karen Andreasen
     
/s/ Richard Von Hor
 
Richard Von Hor
     
/s/ Danny Ewing
 
Danny Ewing

 
-17-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Thomas McGovern
 
Thomas McGovern

 
-18-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Kenneth Keska
 
Kenneth Keska

 
-19-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
R & R Opportunity Fund
     
By: /s/ John J. Borer, III
 
John J. Borer, III
 
Authorized Signatory

 
-20-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.
 

 
BUYERS:
     
Dolphin Offshore Partners, L.P.
     
By: /s/ Peter E. Salas
 
Peter E. Salas
 
General Partner

 
-21-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Thomas Peckosh
 
Thomas Peckosh

 
-22-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Charles R. Skemp
 
Charles R. Skemp

 
-23-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Charles Gwirtsman
 
Charles Gwirtsman

 
-24-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
GCA Strategic Investment Fund Limited
     
By: /s/ Lewis N. Lester
 
Lewis N. Lester
 
Authorized Signatory

 
-25-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
Maythorpe Holdings Limited
     
By: /s/ Joel Handel
 
Joel Handel
 
Authorized Signatory

 
-26-

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
or caused their duly authorized officers to execute this Agreement as of the
date first above written.

 
BUYERS:
     
/s/ Myron Wick, III
 
Myron Wick, III

 
-27-

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Exhibit A

Plan of Distribution

The selling stockholders, which as used herein includes donees, pledgees,
transferees or other successors-in-interest selling shares of common stock or
interests in shares of common stock received after the date of this prospectus
from a selling stockholder as a gift, pledge, partnership distribution or other
transfer, may, from time to time, sell, transfer or otherwise dispose of any or
all of their shares of common stock or interests in shares of common stock on
any stock exchange, market or trading facility on which the shares are traded or
in private transactions. These dispositions may be at fixed prices, at
prevailing market prices at the time of sale, at prices related to the
prevailing market price, at varying prices determined at the time of sale, or at
negotiated prices.

The selling stockholders may use any one or more of the following methods when
disposing of shares or interests therein:

- ordinary brokerage transactions and transactions in which the broker-dealer
solicits purchasers;

- block trades in which the broker-dealer will attempt to sell the shares as
agent, but may position and resell a portion of the block as principal to
facilitate the transaction;

- purchases by a broker-dealer as principal and resale by the broker-dealer for
its account;

- an exchange distribution in accordance with the rules of the applicable
exchange;

- privately negotiated transactions;

- short sales effected after the date the registration statement of which this
Prospectus is a part is declared effective by the SEC;

- through the writing or settlement of options or other hedging transactions,
whether through an options exchange or otherwise;

- broker-dealers may agree with the selling stockholders to sell a specified
number of such shares at a stipulated price per share; and

- a combination of any such methods of sale.

The selling stockholders may, from time to time, pledge or grant a security
interest in some or all of the shares of common stock owned by them and, if they
default in the performance of their secured obligations, the pledgees or secured
parties may offer and sell the shares of common stock, from time to time, under
this prospectus, or under an amendment to this prospectus under Rule 424(b)(3)
or other applicable provision of the Securities Act amending the list of selling
stockholders to include the pledgee, transferee or other successors in interest
as selling stockholders under this prospectus. The selling stockholders also may
transfer the shares of common stock in other circumstances, in which case the
transferees, pledgees or other successors in interest will be the selling
beneficial owners for purposes of this prospectus.

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In connection with the sale of our common stock or interests therein, the
selling stockholders may enter into hedging transactions with broker-dealers or
other financial institutions, which may in turn engage in short sales of the
common stock in the course of hedging the positions they assume. The selling
stockholders may also sell shares of our common stock short and deliver these
securities to close out their short positions, or loan or pledge the common
stock to broker-dealers that in turn may sell these securities. The selling
stockholders may also enter into option or other transactions with
broker-dealers or other financial institutions or the creation of one or more
derivative securities which require the delivery to such broker-dealer or other
financial institution of shares offered by this prospectus, which shares such
broker-dealer or other financial institution may resell pursuant to this
prospectus (as supplemented or amended to reflect such transaction).

The aggregate proceeds to the selling stockholders from the sale of the common
stock offered by them will be the purchase price of the common stock less
discounts or commissions, if any. Each of the selling stockholders reserves the
right to accept and, together with their agents from time to time, to reject, in
whole or in part, any proposed purchase of common stock to be made directly or
through agents. We will not receive any of the proceeds from this offering.

The selling stockholders also may resell all or a portion of the shares in open
market transactions in reliance upon Rule 144 under the Securities Act of 1933,
provided that they meet the criteria and conform to the requirements of that
rule.

The selling stockholders and any underwriters, broker-dealers or agents that
participate in the sale of the common stock or interests therein may be
"underwriters" within the meaning of Section 2(11) of the Securities Act. Any
discounts, commissions, concessions or profit they earn on any resale of the
shares may be underwriting discounts and commissions under the Securities Act.
Selling stockholders who are "underwriters" within the meaning of Section 2(11)
of the Securities Act will be subject to the prospectus delivery requirements of
the Securities Act.

To the extent required, the shares of our common stock to be sold, the names of
the selling stockholders, the respective purchase prices and public offering
prices, the names of any agents, dealer or underwriter, any applicable
commissions or discounts with respect to a particular offer will be set forth in
an accompanying prospectus supplement or, if appropriate, a post-effective
amendment to the registration statement that includes this prospectus.

In order to comply with the securities laws of some states, if applicable, the
common stock may be sold in these jurisdictions only through registered or
licensed brokers or dealers. In addition, in some states the common stock may
not be sold unless it has been registered or qualified for sale or an exemption
from registration or qualification requirements is available and is complied
with.

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We have advised the selling stockholders that the anti-manipulation rules of
Regulation M under the Exchange Act may apply to sales of shares in the market
and to the activities of the selling stockholders and their affiliates. In
addition, to the extent applicable we will make copies of this prospectus (as it
may be supplemented or amended from time to time) available to the selling
stockholders for the purpose of satisfying the prospectus delivery requirements
of the Securities Act. The selling stockholders may indemnify any broker-dealer
that participates in transactions involving the sale of the shares against
certain liabilities, including liabilities arising under the Securities Act.

We have agreed to indemnify the selling stockholders against liabilities,
including liabilities under the Securities Act and state securities laws,
relating to the registration of the shares offered by this prospectus.

We have agreed with the selling stockholders to keep the registration statement
of which this prospectus constitutes a part effective until the earlier of (1)
such time as all of the shares covered by this prospectus have been disposed of
pursuant to and in accordance with the registration statement or (2) the date on
which the shares may be sold without restriction pursuant to Rule 144 of the
Securities Act.

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